First thing is to not make it a phase or something you're going to do until you see results and then slack off, that's when you hit it harder. The biggest issue is a healthy diet, and you can't think "I'll just diet for a while and be ok to lose weight". No you won't, you'll rebound and in most cases you'll end up heavier. It takes dedication to eat right and workout even if you're only working out a few times a week, it's a lifestyle. On the bright side you eventually will stop craving fast food and become nauseated by the smell (I can't even go into a Burger King parking lot anymore without getting nauseous). I'm 42, have a physically demanding job, eat right and do at least a light work out 3-5 days a week and at 6'1" and 200lbs I might not be in the best shape of my life but I think I look better now than I did when I was in my 20's-30's and I'm in better shape than a lot of people half my age. I'm not genetically gifted other than being able to throw a baseball and I can't gain muscle mass no matter what I try (I get stronger, just not noticeably bigger) and I have my wife to thank for it. My wife is a fitness specialist for Advocate Healthcare and because of her I eat even better than I ever did and eating better gave me the extra energy after climbing poles all day to be able to work out after the type of day that would cripple most people. Age doesn't necessarily mean it'll take longer to recover with the exception of a hangover, as long as your diet is right and your body is used to the stress it doesn't take much longer to recover from a hard workout, or at least it doesn't feel like it.
It's pretty much as simple as eat right, take vitamins/supplements and never stop working out a few times a week.
