how to...

[esskreemr]

Yes, Mergs is correct. I've tried everything from spray on lacquer, to plasti-dip to spray-on truck bed lining (available at Wal_mart, makes a nice textured grip). Prepare the surface by sanding it with a medium grit, and protect your grips when they are in your bag else they will get chipped.

[dreamer90024]

just any old kind of spray paint seems to work. I don't think you need anything special.

[Mergs]

Some work much better than others. If you clean the grip, I would suggest Rustoleum or other such paint specifically formulated for metals/outside furniture.