I always apply, buff, wash, dry (whatever) my products with a "back and forth" motion. I've always done it this way (since I became a Autopia member) 
But, recently I've read some posts where people use a "up and down" technique on the sides of the car.
Should I be doing this??? Have I been hurting anything bye going "back and forth":nixweiss
But, recently I've read some posts where people use a "up and down" technique on the sides of the car.
Should I be doing this??? Have I been hurting anything bye going "back and forth":nixweiss