Alrighty bro, I just did this mod myself so I will step by step it since it is still fresh in my mind....
1. Open your trunk lid. You will see little black plastic things holding the trunk liner in place. Take a flat head screw driver and pop them out. DONT LOOSE THEM. Remove trunk liner ("carpet")...
2. Close trunk lid and carefully align the template that comes with the spoiler.
3. Double check your template alignment.
4. Triple check your template alignment.
5. On the template you will see a set of 'circles' on the tabs. That is where you take a small drill bit and drill into your trunk lid.
6. Once your holes are drilled, take off the template and apply small dobs of primer to the exposed metal on both sides of the holes. (inside the lid and out) To prevent rust 5 years from now.
7. Take your spoiler and insert the bolts into the holes.
8. Tighten all the nuts.
9. Reinstall your trunk liner with plastic pieces.
10. Close trunk lid and stand back to admire your handy work.
11. Take pictures and post them on TN.
Rear spoiler w/ pic
Good luck!!