You need to leave a good “tail” of material past the tack strip area, so that you have something to pull with to stretch material.
Mark centerlines on top material (chalk is fine), mark centerline on top of car (I use the blue painter tape then mark on the tape, this tape will pull up from painted surface with no problem).
Tack center of material at the front, in two or three places within 8-10 inches of center. Go to back of car, line up centerline, pull snug and repeat at back of car. Do the center of the sides the same way. then, working a foot or two at a time, tack down the front, the rear, then move to each side, and repeat, pulling taut as you go.
The best way to cut the excess material without harming paint is to:
-with scissors, cut a slit in excess material up to the tack line
-take a single edged razor blade, and pressing it down next to slit and in line with tack line (where you want the edge of material to end up), pull up on the excess material against the blade, cutting it.
-Move blade and repeat. It takes a few minutes to do it this way but you won’t harm paint.
David Coco Winchester Va.