Here you will find lots of good-practice advice for working at the PC in your office, your home set-up and your laptop - wherever you use it.or a good start, have a work through Birkbeck's interactive computer workstation safety training package. It takes only around 20 minutes and could save you hours of discomfort! Try the quiz and see what score you get. If you manage to get 100% contact the College Safety Officer for a prize.
This site is very good with regard to adopting best posture when sitting.
You could also try out the stretching exercises at the following link: