I have a whole method to parking. I did/still do this with my Grand Am, and it is silver, and I had no dings from parking (before I took ownership it had a few, and I know exactly where they are), but DO NOT Parallel park! My only marks were from this, small, small marks, but on silver you can't see it...
On the GTI my anal parking has gotten 100 times worse.. I also do an end spot at the office, curb/island on the passenger side/car passenger side to your left - most people are driving themselves, no passenger door to hit your driver's side!
Or if I must park next to a car...sometimes unavoidable, stay away from the following:
MiniVans
Beat up cars
Coupe's (unless its a sports car, porsche, Ferarri etc)
A car with already dings in it
ANY SUV that looks like it has kids!
I follow this rule and it seems to work! "Nice" cars aren't always nice.. you see a nice 7 series...remember it has HUGE doors, and a good, good chance the passenger could be a kid...so park on the drivers side of these!
Also, since the GTI is more of an enthusiast car, if you see another GTI, park next to it! (or GLI or anyone sporting a VW with some flare).
My wife calls me crazy, but it works!