BigLump said..
If the tape happens to produce a black mark (very rarely) I use another one of DJ's tips, "magic eraser", to remove the marks.
Or just use a tape of the general color of the rails as the last tape layer.
Any color in fact, I use different colors for each paddle to tell them apart quickly, and it seems that only the black ones leave marks.
I tend to use orange, red for my surf paddle, handy to find the paddle if you lose it.
Alas, here I can only find the quality tapes (3M) in black, so I use black 3M for the fist layer to insure proper adhesion to the blade and finish by a colored cheap one.
Another trick: use a wide one for the lower layer, and narrower ones for the top layers if you are anal about performance, to get a nice progressive thickness.