Q: how do i gain muscle being so skinny?

A: Believe it or not, you're actually in the PERFECT position to gain muscle! What you'll need to do though is eat big and lift big. Without lots of food you'll never build a whole lot of muscle, but with a good workout and a good diet program, the sky's the limit. You can realistically shoot for as much as 20-25 pounds of muscle gained in your first year of good training and eating. Fill out http://www.mikesfitness.com/content/fitnessguide specifying 'Build Muscle' as your goal and see what kind of training and eating it'll take. Good luck and remember: if you're not gaining weight -- EAT MORE!