well as for the grey scotching so the metalics sit flat is in a circular motion asif ur waxing a car say for instants tarond the tail light youve got the lips and edges corners etc you wont be able to use a tool for this except your hand and some grey scotch.also any groves such as were the wiper arms attatch to,the were the arch curves on the wing and just below window appertures.erm yes a clean car is a good idea but not really to necassary as you are doing a full respray.and all i wouldnt do anythink at home because if weather turns nasty ur screwed what ever you start to do.as long as you key the surface primer up well the flakes will lay nice and flat.where are you based btw?i may be able to give you a hand