Clean area where the deal will be applied thoroughly with rubbing alcohol/wipe and let dry.
Carefully peel backing paper off the decal. The decal should remain on the transfer tape.
Position decal where you want it using a rigid card, like a credit card or gift card, slowly with pressure, rub decal to make it adhere to the surface. Work your way from the center towards the edges, especially on sharp points.
Slowly peel away transfer tape at a low angle. Do this slowly to ensure the decal remains on the surface and releases from the transfer tape. If there are issues, place decal and type down, go back to step 3
* If necessary, pop air bubbles with a sharp pin or needle then press to remove air