>Having just had a new baby I am finding that I'm getting only a few hours sleep at a time and unfortunately when I'm tired, I get anxious.
Luckily I have my yoga practice to help me out - I don't get much time to get on my mat but I do have time to breathe so am making sure I take out 10 minutes to lie down and take some deep breaths.
Once I feel a little calmer I start to focus all my attention on the rise and fall of my breath. Often my mind will wander and when I notice that happening I gently bring my focus back to the breath and the movement of my belly going up and down (so I'm using my full lung capacity).
The key is to be patient with yourself, the fact that your mind WILL wander and be kind when your mind is whirring.