Get a physical with a echo stress test
to make sure you are in good health.
Loss weight if you need to (when I was doing my psychology internship in the cardiology department (long story) all the doctors like weight watchers best for this...
Ask your doctor if you are healthy enough to walk 30 mins per day - and walk fast enough to get your heart rate
Eat only a few ounces of meat in any meal
Increase your intake of fruits and vegetables.
Decrease use of Butter, Milk (except skim), and Cheese
reduce stress - there are lots of good books on this....
have at least one good friend you can share things with - personal things.
Laugh more - it really is good medicine.