Some mineral spirits or paint thinner to get rid of excessive glue. Take a razr blade, after sticker is gone, to get ride of the glue..Thats what i did...
-take sticker off
-rub mineral spirits/paint thinner to break up some glue
-razr blade it gentle.
don't rub it with a razor blade or any type of thinner... thats just a plain bad idea. think about it your putting paint thinner on your paint.
go get a drill and a 3m sticker remover wheel like todd said. its like a gum eraser but on a shaft. be careful because you can burn thru the paint.