HOW!!! the freak did you do that? I'm especially curious about the upper body and the lower abs... ABSolutely no trace of you being any bigger (that is, no stretch marks, no loose skin). It's as if you were fit from Day 1 (the day you were born).
What did you [not] do? How did you eat? How did you work out?
Well, as far as diet, I became very strict. I completely got rid of junk for quite a while (I tend to treat myself here and there now though). I've never been particularly disciplined in exercise, but when I lost the bulk of it doing 45 min cardio, and moderate weights. main piece of advice would be to do your research, if you are serious about healthy eating, now as much as you can about it, including fats, protein, carbs, basically...know your way around the nutrition facts.
Good advice, although a great thing to do is always consult boards like this, because going it alone often kills or hinders progress for most, as many do it wrongly, and don't know what they're doing.
When you've seen people having meals with 2OZ Salmon and a few Beans, or one Apple as a snack or just 1 Egg, you know they're trying but getting a bit lost along the way.
Boards like this don't give you 100% accurate info for 100% of peoples needs, but often they can be sources of good info, without you necessarily feeling obliged to pay for it, especially if some people can't afford that advice.