counting the breaths is one of the beginning meditation methods taught by the Zen schools (not sure if both Soto and Rinzai use it - it may just be Rinzai). the idea is that as you breathe, you count - first breath is one, second is two, and so on. if you notice that you're doing something other than counting, you go back to one. the goal isn't so much to get to 10 (or 50 or 10000 or whatever) - you're not consciously trying to prevent yourself from counting, you're just aware that at some point your attention will wander off, and at that point you start over.

or something like that.