Make sure that you take breaks properly. If you’re taking too many breaks or you’re spending your time relaxing and doing things you won’t be able to accomplish as much as you should. This means that you’ll fall behind in your work and you’ll be completely reversing anything that you may have benefited by taking a break.  

Instead take several short breaks. You should try to work for around 30 minutes and then you can take 5 minutes to get up, walk around, stretch out and get back to work. This will give your brain a little time to refresh and relax. You’ll get to breathe and look away from those papers or that computer screen. Now, if you want to take a long break you’ll generally need to work a little longer. Try to work for a couple hours (while still taking short breaks) and then take a half hour away from your work. This will help you get rid of some of that excess stress (plus it lets you have a little fun).