Originally posted by Jack Smash
I used the stock protoform mask for the windows but i used 1/8th" fine lin tape around the inside of the protoform mask and traced it with my xacto knife. Some guys free hand it but im not that good at gettin a consistent width so I use the tape as a guide. Then when your done painting the rest of the body, pull up the fine tape and the mask beneath it and paint whatever color for the window trim.
Sometimes, i won't use the included masks, and will just use Liquid Mask.
Most of the time, i take a sharpie, draw where i need to cut the outline, then use the X-acto.
Remember, measure twice, cut once.