Ergonomics are very important if you will be spending any length of time at this workstation.
I'm no ergonomics expert, but I did the following and it worked well for me:
- Start with your listening position, and get your chair height right. Your feet should be flat on the floor when your knees are at a 90 degree angle
- when sitting up straight with your knees at a 90 degree angle, let your arms hang loosely from your shoulders with your elbows at a 90 degree angle. The keyboard and mouse height should be here.
Etc etc. The good thing about DIY is you can build a workstation to fit yourself.