We all know that using a computer for a longer time each day, makes your eyes tired. This is a simple rule which may help reduce your eyestrain and let your eyes relax for a while. It is recommended to stand up and stretch once in a while without sitting on your chair all the time. But sometimes it may not be possible to walk in every 30 minutes from your chair. But at least try following 20-20-20 rule to relax your eyes :)
20-20-20 rule:
And try to blink your eyes more so that it will help your eyes to avoid getting dry.