Daniel, as the others have mentioned the key is ultra thin. The foam applicator will enable you to do that easier. Put a light amount on the applicator, then starting at a corner of the panel spread the wax as far as it will go - until the applicator leaves nothing behind. Then repeat. You'll find that after several applications the pad gets loaded up and requires much less wax. Remember, less is more with all waxes.
Allow it to haze, swipe your finger on the hazed wax and see if wipes off easily. If it smears, even slightly, give it another few minutes and check again. Remove with a quality MF towel. You may need several, as they get clogged with wax pretty easily and have trouble clearing the surface. After removing all the residue, go over the car with a clean MF and give it a good (light) polish.
Also, ensure the surface has been clayed and cleaned with a prewax cleaner like Megs Step 1. This will give a better result to the appearance, durability, and wax removal. If the surface is swirled/scratched, you may need to polish instead of prewax clean. :up