Regular vacuuming and dusting of your car's interior is the best way to keep it looking good.  However, surface cleaning alone is not enough.  Two to three times a year you will need to detail the upholstery to keep it looking its best.

Warning: Before using any product on your car's fabric upholstery, carpet, leather or vinyl, test for color fading by cleaning a small, inconspicuous area.  Do not use the product if it adversely changes your fabric's color or texture.

A SYSTEMATIC APPROACH
The interior of your car takes a lot of abuse.  Unlike the inside of your home, which has many times more square footage, the inside of your car gets repeated, concentrated traffic.  Each time you get in your car, you drag in more dirt.  Each time you eat or drink in your car, you add a few more crumbs and spills.  In fact, just sitting in your car, you drop hair, dead skin, makeup and other contaminants.  All of this dirt and junk adds up very fast.

It is not necessary to fully detail the inside of your car each time you wash it.  Unless you've been to the beach, out in the mud, or tracking in grass and leaves, you can probably get away with vacuuming and a quick wipe-down every couple of weeks.

Weekly Interior Cleanup
Here's what I recommend as a weekly routine for the interior:

1. Wipe down all vinyl, leather and plastic surfaces with a damp cloth.  A microfiber detailing towel is excellent for this task, as it will leave a lint-free, dust-free finish.
   
   

2. Pull out your floor mats, and shake or brush off the dirt and debris.
   
   

3. Pick up trash (that old banana peel you tossed into the backseat), and empty the ashtray and console storage bins.
   
   

4. Wipe down your door jambs and doorsills with a damp towel.
   
   

5. Wipe down your interior glass and your rearview mirror with a damp microfiber detailing towel.  If your windows are relatively clean, you don't need to use a glass cleaner.

Very recently, a new product category has emerged for the car interior that's equivalent to the exterior quick detailing spray.  Interior cockpit sprays, like Sonus Cockpit Detailer, combine light cleaning and protective capabilities in a spray-and-wipe system.  If you're looking for an interior product that keeps your cockpit looking perfect, you might give it a try.  In my mind, this is a much better solution than layer after layer of protectant.

Monthly Interior Detailing
Once a month your car's interior will need a little more than a quick wipe-down.  After a month, your interior glass will have some film buildup, the carpet will need to be vacuumed, and the dash, console and other vinyl parts will need to have their protection renewed.  Here's what I recommend:

1. Follow all of the steps for the Weekly Interior Cleanup.
   
   

2. Vacuum the interior carpet, seats, seat crevices and console.
   
   

3. Clean the interior glass with a good glass cleaner and a  microfiber detailing towel.
   
   

4. Apply a vinyl protectant with an ultraviolet (UV) light inhibitor to the dash, console and tops of door panels (the areas with the most sun exposure).  I find that a foam applicator works the best.

PROPER INTERIOR DETAILING
With the variety of materials used inside the modern automotive interior, knowing what to detail and how to do it is not always  a straightforward matter.  This section is divided into specific materials and areas of interior detailing.  Read the areas that apply to your vehicle.  

Vacuuming
There's no special science to car vacuuming.  You need a good vacuum, a few attachments, and ten to fifteen minutes to get in there and get the job done.

The two most important attachments are the crevice attachment and the dust brush attachment.  Make sure your crevice attachment is plastic, not metal.  A metal attachment or a plastic attachment that's in poor condition may scratch or otherwise damage leather or vinyl upholstery.

Use the crevice tool to reach between and under seats, into tight seams, nooks and crannies, and around seat beads.  Vigorous movement on the carpet helps to bring up sand and grit.

Use the round dust brush attachment to vacuum the console, dash and vents.  You can assist with the dusting by using an interior detailing brush ahead of the vacuum to get deep into vents and cracks.

Here are the steps for proper vacuuming:

1. Start your vacuuming job by pulling out the floor mats.  Shake out the mats to remove any loose dirt.  Use a 4" upholstery attachment or the bare hose end to vigorously vacuum the mats.
   
   

2. Work on the rear upholstery and carpet.  Push the front seats all the way forward.  Use the crevice tool to vacuum the cracks of the seats, and between the seats and carpeted areas.  If the seat upholstery is fabric, switch to the 4" upholstery attachment and vacuum the rear seat and the deck under the rear window.  Vacuum the rear carpet.  Use the crevice tool to vacuum around the seat tracks and under the front seats.  Use the round dust brush attachment to vacuum the door panels.
   
   

3. Push the front seats all the way back to work on the front upholstery.  Use the crevice tool to vacuum the cracks of the seats, between the seats and carpeted areas, and around the gas and brake pedals.  Now switch to the 4" upholstery attachment to vacuum the carpet in the foot wells and the seats (if the seats are fabric).  Use the round dust brush attachment to vacuum the console, vents and door panels.
   
   

4. If your headliner is fabric, use the round dust brush attachment to vacuum the headliner.  Be gentle, though, as this material is not as durable as your seat upholstery.

Tip: When vacuuming carpet, use the palm of your free hand to beat the carpet just in front of your vacuum hose or tool.  As you beat the carpet, dirt that is lodged deep into the carpet will come loose for vacuuming.

Dashboard & Console  
We look at the dashboard and console more than any other area of our car's interior.  It makes sense, therefore, that we should give it some special attention.  The dash and the deck under the rear window also take the brunt of damage from sun exposure.  In order to keep your dash from cracking and fading, regular treatment is necessary.

Caring for the dash and console is really pretty easy.  Simply wipe them down with a damp towel every time you wash your car, and treat them with a vinyl protectant once a month.  To reduce the effects of the sun's UV rays, use products like 303 Aerospace Protectant or Sonus Total Eclipse, which contain protective UV sunscreens.  These are my personal favorites because they create a nice satin finish.

The easiest way to treat the dash and console is to use a foam applicator pad.  Spray your vinyl protectant on the applicator, not on the dash or console, and wipe it in thoroughly.  This will prevent overspray on your glass and upholstery.  Don't forget to protect the steering wheel, turn signal levers and the shift boot.  Allow the vinyl protectant to soak in for 3 to 5 minutes, and then buff the dash and console dry with a microfiber detailing towel.

If you're doing a complete interior detail, you should also dust and clean out the vents and grillwork.  There are a variety of tools that work in vents and grilles.  The easiest are a small detailing brush and compressed air.  If you don't have compressed air, you can use the blow cycle on your vacuum.

If your vents are disgustingly dirty, use a cotton swab or foam swab (electronics part-cleaning swabs from Radio Shack) to clean out the dirt.  A good vinyl cleaner and protectant, works well on a foam swab to clean and beautify vents and speaker grilles.

On consoles with a lot of nooks and crannies, it's best to use an old toothbrush followed by a towel to clean and protect.  This same method works well around buttons and controls on the dash.  Aerosol products like Stoner Trim Shine also work well in detailing areas and spots where your towel and finger can't reach.

Door Panels & Jambs
Door panels are often made of several materials, including fabric, vinyl, carpet and leather.  Vinyl can be scrubbed to remove shoe scuffs.  General-purpose cleaners, like 303 Aerospace Cleaner, or interior vinyl and plastic cleaners, like Sonus ALL-IN-1 Total Auto Cleaner,  easily remove black scuff marks from these areas.

Vinyl & Plastic
Vinyl and plastic are the most durable interior materials, but they do need frequent cleaning.  Unlike cloth, the surfaces of vinyl and plastic generate static, which tends to attract dust.  As a result, vinyl and plastic become grimy.  The good news is, vinyl and plastic are the easiest surfaces to clean.

Do not use regular household soap and water on your vinyl and plastic surfaces.  Detergent will permanently remove the sheen from vinyl and plastic.  Choose a cleaner made specifically for interior vinyl and plastic.  One of my personal favorites is Stoner Trim Cleaner, which is a quick spray-and-wipe solution that does not require rinsing.

Follow these easy steps for the perfect vinyl interior:

1. Spray vinyl, plastic and imitation leather  surfaces with your favorite cleaner.
   
   

2. Work the cleaning solution into seams, edges and seat backs with a sponge or cleaning cloth.  If you have stubborn dirt, use an upholstery scrub brush.  If necessary, use an old toothbrush to get into the small crevices.
   
   

3. If your cleaner requires rinsing, wash the vinyl and plastic  thoroughly with fresh water and a clean microfiber detailing towel.
   
   

4. Dry the upholstery with a clean, dry microfiber detailing towel.
   
   

5. Allow the vinyl and plastic to dry, and then apply your favorite vinyl dressing to restore protection and sheen.

1. Vacuum the upholstery thoroughly.
   
   

2. Spray spots and heavily soiled areas with a good spot remover, and allow the cleaner a few minutes to work.  I use 303 Carpet & Upholstery Cleaner.  If you like a foaming cleaner, I recommend Stoner Upholstery & Carpet Cleaner.
   
   

3. Fill a bucket with 2 gallons of warm water.
   
   

4. Lightly spray a section of upholstery (no more than 2 square feet at a time) with your upholstery cleaner.  Use an upholstery scrub brush and a sponge in a circular motion to agitate the upholstery.  Dip your brush in water to keep it wet, but apply as little water as possible.
   
   

5. Wipe away the suds with a sponge or a damp detailing towel.
   
   

6. Empty your bucket of soapy water and refill with clean warm water.
   
   

7. Rinse the upholstery with clean water by wiping with a damp terry cloth towel or sponge.  Rinse the soap from your towel or sponge often and wring it out.  Use as little water as possible, but rinse thoroughly.
   
   

8. Vacuum your upholstery to extract the remaining rinse water and dirt.
   
   

9. If you're not working on a warm, sunny day, use a hair dryer to complete the drying process.  Be careful not to scorch the fabric by holding the dryer too close.
   
   

10. Allow the fabric to dry overnight before using the vehicle.  If possible, keep your windows open slightly to allow the moisture to escape.

To keep your fabric upholstery looking factory fresh for many years, consider using a fabric protectant, such as 303 High Tech Fabric Guard.   It blocks the sun's damaging rays and repels water, oil, grease and dirt.  Use a fabric guard only on new or just-cleaned upholstery.  Your upholstery must be dry.   Simply spray it on (two light coats is better than one) and let it dry.  If you have a convertible with a fabric top, you can use Wolfstein's RaggTopp Protectant for both your interior fabric (cloth and carpet) and your top.

Carpets & Floor Mats
Most automotive carpets are very durable and will withstand repeated shampooing without signs of damage or wear.  Carpet cleaning is not fast or easy.  You should expect to spend 2 to 3 hours shampooing the front and rear carpet and mats in a sedan or SUV, a little less time for a truck or two-seater.

Before shampooing, the carpet and floor mats must be thoroughly vacuumed.  To do a complete job, it may be necessary to remove the front seats, which requires the correct size Allen or socket wrench.

Follow these easy steps:

1. Spray spots and heavily soiled areas with a good spot remover.  I recommend a product like 303 Carpet & Upholstery Cleaner or Stoner Upholstery & Carpet Cleaner.
   
   

2. Fill a bucket with 2 gallons of warm water.
   
   

3. Lightly spray a section of carpet (no more than 2 square feet at a time) with your carpet and upholstery cleaner.  Use an upholstery brush or a sponge in a circular motion to agitate the upholstery.  Dip your brush in water to keep it wet, but apply as little water as possible.
   
   

4. Wipe away the suds with a sponge or a damp detailing towel.
   
   

5. Empty your bucket of soapy water and refill with clean, warm water.
   
   

6. Rinse your carpet with clean water by wiping with a damp terry cloth towel.  Rinse the soap from your towel often and wring it out.  Use as little water as possible, but rinse thoroughly.
   
   

7. Vacuum your carpet to extract the remaining rinse water.
   
   

8. If you're not working on a warm, sunny day, use a hair dryer to complete the drying process.  Be careful not to scorch the carpet by holding the dryer too close.
   
   

9. Allow the carpet to dry overnight before using.

To keep your carpet and floor mats looking great, use a fabric protectant like 303 High Tech Fabric Guard.  It's really cheap insurance against spills and stains.

INTERIOR STAINS & ODORS
With our active lifestyles and the amount of time we spend in our cars, the average car interior is easy prey for a myriad of stains and odors.  Stain and odor removal is almost a science unto itself.  Upholstery fabrics and carpets vary widely, as do the types of stains.  However, in my experience, there is a correct method and a suitable cleaner for most car interior problems.

Protection Is Worth a Pound of Cure
Common upholstery fabrics are more likely to stain than vinyl or leather.  To best prevent stains altogether, it is necessary to properly treat upholstery, carpet, vinyl and leather.  The best treatment for carpet and fabric is a spray-on fabric guard product.  To protect vinyl and leather, simply use your favorite cleaner and protectant on a regular basis.

When the inevitable happens, and your three-year-old drops (or barfs!) his mustard-loaded hot dog on your brand-new velour upholstery, stay calm.  Remove as much of the spill as possible by blotting, not wiping, with paper napkins, paper towels, etc.  Don't let the stain sit too long before you get to work on it.  Within a day or two, most spills will set and permanently stain your upholstery, or become very difficult to remove.  It will only take one such incident for you to realize that a $15 investment in fabric and carpet protection is worth every penny.  

Stain Removal Basics
Even without protection, you would be amazed at how easy it is to clean up most stains with nothing more than a neutral detergent and water.  A neutral detergent has a pH of 7 (on a scale of 0 to 14).  A detergent with a pH of less than 7 means it is acidic, whereas a pH higher than 7 is alkaline.  Neutral detergents will not bleach fabric or remove fabric protection.

Tools you’ll need to remove interior stains include:

• Spatula or putty knife

• Clean, white terry cloth towels

• Upholstery scrub brush

• Wet-dry vacuum

• A reliable interior stain remover, such as 303 Carpet & Upholstery Cleaner

Use the spatula or putty knife to remove as much of the solid material as possible.  The vacuum can also be a lifesaver by removing large particles of any substance that would stain if you rubbed it or moved it around.  The idea is to remove as much of the contamination as possible before you begin wiping or scrubbing.