I find that the more I move around, the better I get. So I make a point to be up moving for at least 15 minutes every hour or two. Start slow if you need to work up to more time.
Remember to be conscious of your posture. It has helped me tremendously with my balance to line up my shoulders over my hips and think of an imaginary string holding my head on the top.
If you can't get up and walk, try to move your arms and legs around often. Moving also helps me think more clealy.
I'm sorry for the long book lol. Hope some of these things help you.

Everything LisaMintz Said I would recommend as well.

Thank you