Exercises for patellar tendonitis?

After a doctor's visit yesterday, I was diagnosed with patellar tendonitis. I was told that walking on a level surface was good, but to avoid stairs or hills. Do any of you know of any further exercises/treatment I could do to hasten the healing? I have an infrared heating wrap, and was given an anti-inflammatory. It doesn't hurt normally, just when I climb stairs and stand up from a kneeling position when filing at work. Thanks for your answers.