Control stress when you can, both at work and at home. Learn some techniques to relax. Try to exercise every day, and leave enough time to rest at night.
Scrapes and sunburns can trigger psoriasis, so be gentle when you scratch your head. Wear sunscreen and a hat when you go outdoors.
To lower chances that you'll get strep throat or another illness, wash your hands often -- and don't share forks or spoons with others.