Tinting Windows

Ok my car had 35% tint on all but the drivers door and windshield and I pulled it all out and cleaned my windows last night so I could install new tint (doing it myself) so I was just wondering if any of you had any tips on doing a job good or if you have any pics of cars with 20% or maybe even 5%?
I am thinking I will go with 20% all around and 2 1/2% on the sunroof but I want to see how dark 20% would be, and I will have a local shop do the rear hatch glass for me. And instead of tinting over the dot matrix on the 3 rear windows I will have the tint stop just before the dots and paint the dots with some flat black paint so I won't have to worry about the tint slowly rising due to being over the dots like my old tint was.
Anyways any tips, pics or suggestions will be appreciated.