Nope.
Basically it cuts everything... you peel out the parts you want subtracted. Then you apply a top(masking tape like) application ontop of it which then allows you to apply it to your soon to be sand blasted piece. Peel off the top sheet and your good to go.
Its all real easy, maybe my explanation makes it sound like a pain.

nah, this is how i did my first one which i didnt plan great, the second one i did right on the glass, this thing looks amazing but it is pretty pricy, if i really go crazy maybe ill save for one, itd really multiply my possibilities i appreciate the info thanks a bunch!