Question:  Does anyone know the proper way to put a hood decal on?

Very carefully! Actually, the question should be “Did you purchase the right decal material, and if not, why not?” It is very important when dealing with large decals covering an area with multiple curvatures such as almost every part of an automobile that you use a decal material that is meant to be installed over this type of substrate.

1. Consider the type of decal you have.

If you purchased a decal made of a vinyl decal material that was intended to be installed on a flat surface such as a window or a flat sign face,

Question:  Should I put a decal on the hood of my car before or after I wax it?

Yes. You can do either without any problems, although there are some who advocate stripping the car down and waxing it first because then, when you want to remove the sticker, it is not going to have an area that looks different from the waxed area where the decal came from.