I've been working out almost every single day since I started college and I managed to gain 20lbs of muscle (140lbs to160lbs) in 6 months. During the first few months I only would run a couple of miles and that just helped me trim the little fat I had. In the past 2 months I've began some serious weight lifting and ab routines. I take GNC wheybolic protein which really helps me pump up. My routine is pretty sloppy though since I'm not really consistent with balancing out what I'm focusing on, but I'm learning.
I also have given up greasy food completely except for the traditional White Castle after every concert when I'm home.