Here is a "Basics of Basics" on the subject, Basics Of Basics - Autobodystore
One thing you need to be careful with is when you get it loose and are pulling up on it, you REALLY need to watch that the other end isn't coming back down and hitting the paint. It's riding up on a little piece of foam right, so if you tilt it up pulling it off, the edge of the other end can come down and hit the paint marring it.
I didn't have much success with the floss, but maybe a different brand? One thing that worked pretty good was that plastic banding they put on cardboard boxes, that stuff sawed thru and worked pretty good.