Excellent question! Your are correct. Diet,exercise, one a day vitamins, good hydration, no smoking (no secondary smoke), controlled alcohol (one drink a day), no street drugs, good hygiene, controlled medical problems, medical clearance, proper hydration (water), minimize stress, sufficient sleep, etc.
Occasionally a medical issue is uncovered with pre admission testing. Any new medical issue certainly needs follow up before surgery.
Consult a Board Certified Plastic Surgeon
Your health habits can make a big difference in how well your surgery goes. It is important to control the things that are within your power to change. Being in good nutritional status is important for wound healing. Do not skimp on protein. Avoid extreme diets in the immediate pre operative period.Vitamins make a difference only if you are deficient in the required amounts. Being aerobically fit will allow a speedy return to full energy. You should be exercising for 30 minutes 3-5 times a week. You also need to be in a good place psychologically to have the resilience to recover from surgery. Surgery should be postponed if you are going through major life stress.