Nothing beats Tamiya tape for masking the edges of a paint job where you want a clean edge. Tamiya tape is a yellow color, but it gets slightly darker when it is cleanly and securely burnished. When you see the color change, you can be pretty sure that you will not have paint creep. A major drawback however is that Tamiya tape is expensive and not readily available SO -
I conserve on the use of Tamiya Tape by using 3M blue tape, BUT LOOK CAREFULLY FOR A MARKING STATING THAT THE TAPE IS FOR DELICATE SURFACES. This is nearly as good as Tamiya tape, but without the color change. It is low tack, but will stick. I make my edge using Tamiya, then cover large areas with the 3M variety. Nothing is more irratating than finding some area of overspray that happened because you were cheap or innatentive with masking, so I use plenty of this stuff, 'cause its cheap.
By the way, when doing compound curves cut the tape into very thin strips to mask the outside line. Then fill in between.
Good Luck
Jimf