The instructions for this practice are simply to start with the number ten, and count backwards silently each time you exhale. When you reach one, count up to ten. Then back down, and up, over and over again. Each time you get distracted, or notice a thought, simply start at ten again, or start with a number nearby. Let it be more like a game, playful and relaxed, rather than a chore.
The following meditation tracks are identical, except that the second track has a longer period of silence.