Make sure your craft is completely dry BEFORE you apply any vinyl lettering or decals. If your craft is not completely dry the transfer tape will peel the paint or tear your paper. Your vinyl comes in three layers: 1-white (or blue) backing, 2-the vinyl, and 3-the transfer tape. Turn your decal face down and burnish well with your squeegee to help the vinyl adhere to the transfer tape and release it from the backing sheet.
Using masking tape or chalk you can mark where you want your decal, make sure you have it centered. Then you can use the masking tape to anchor your decal in place along the top to create a "hinge"
With your decal secured along the top, flip your vinyl up exposing the backing sheet. Peel off your backing sheet, SLOWLY at a sharp 45 degree angle. If your vinyl peels up, roll the backing sheet back down, burnish again and try peeling again. For extra stubborn or small intricate pieces you may need to use your squeegee or a fine tipped tool to help release your backing (it doesn't happen often but it can happen).
With your squeegee, began smoothing your vinyl down from the top. Once in place, burnish the decal WELL with your squeegee.
Again, at a sharp 45 degree angle SLOWLY begin to peel your transfer tape from your vinyl. You may need to use your squeegee to burnish vinyl in place if it comes up with your transfer tape.
TAKE YOUR TIME!
DO NOT RUSH THIS PROCESS. TRYING TO RUSH THROUGH WILL RESULT IN NOTHING GOOD. VINYL TEARS EASILY, STICKS WHERE IT ISN'T SUPPOSED TO AND CAN CAUSE WAY TOO MUCH FRUSTRATION! ALL OF THOSE ISSUES CAN BE RESOLVED BY TAKING YOUR TIME.