If you use a sticky ball, before using it, here are my tips.
Wash it with mild detergent and warm water to remove any oils or manufacturing stuff and dry it with a hair dryer.
Make sure it's pumped up nice and hard too, a really squishy ball is of no use at all.
Wipe the caseback with a lint free pad moistened with shellite or similar to remove any oil residue.
I recently got a couple of balls that had no stickyness at all, the surface was hard and wouldn't grip, even after all of my tricks, I think next door's dog ended up with them.