Clean the surface where the decal is to be fitted thoroughly with Windex or alcohol (ensure that the cleaner does not damage paintwork. It is important that there is no wax or grease on the surface).
Place the decal on the surface and hold in place with a piece of masking tape on one edge so that you can still lift the decal from the surface.
Carefully peel off the backing that is next to the surface that the decal is to be applied to.
Spray a mixture of soap and water or Windex on the area the decal is to be applied. This will help stop air bubbles and allow you to position the decal accurately.
Lay the decal onto the surface, slide it into the position you require and with a credit card, starting at the middle, work out all the liquid.
Leave to dry for 1 to 2 days.
Carefully remove the masking tape and the decal backing, ensuring the decal does not come off with the backing. Do this slowly.
Do not wash the area vigorously for a couple of weeks.
To remove a decal
Use a heat gun to warm the decal and peel it off gently.
To remove any additional glue use rubbing alcohol or similar compound (ensure that this does not mark the paintwork).