I know how you feel. I work online, so I am mostly at home. Anyway, when I got into my mid 20s my metabolism started to really slow down and I started gaining weight so I did a research on diets and came up with the Paleo diet. So I bought this one, it was referred by a friend of mine.
http://cooklikeacaveman.com/paleo-cookbook-review/
3 weeks later, lost 10 pounds already. It's the best thing that I have ever tried.
Practice portion control, don't eat junk, drink plenty of water and take a brisk 30 minute walk every day.