Gentlerock's Diet is best: You can eat anything, just don't swallow!

Seriously, dieting (including using supplements) to slim down is just one aspect. But if you want firm/toned body parts, you have use those muscles (ie. workout). Although dieting is important, it can't firm you up by itself. Working out can be quite a fun social activity too, provided that the environment is right (place, company, etc.).