Are you finding it pleasurable to just be with your breath? Does it seem difficult or too easy?
It is a really deceptively simple activity. One way to think of the practice is that it is like taking a cool drink of water for your mind. You give the mind a break. Let it rest and refresh!
If you find there are lots of thoughts or many sensations, be assured that it is a normal experience. The idea is not to stop thought or stop experience, but to see clearly what is happening, returning kindly and gently again and again to just breathing and being a body.