Hi debpeters56,
Thanks for writing and welcome to alli! Because you have been cleared to by your doctor, ideally you should be exercising on most days of the week for 30-60+ minutes per day, incorporating cardio and strength training into your regimen. Exercises such as the gazelle, biking, walking, swimming, and DVD's such as Taebo, are all very good and effective cardio workouts, and should be performed 4-6 days per week. The alli website provides examples and animated demos for a very good and effective full-body workout Go to "my activity" and then to "strength training log" to view these exercises. Most of these can be performed at home with light-to-moderately heavy weight dumbbells, exercise tubes and a FitBall! Go through these exercises and choose which ones are appropriate for you, performing 2-3 sets of 12-15 reps each.
Good luck and work hard! You can do it!
Best in health,
Kelli