Fitness advice?

I am about to start my third year of college, and I'm not as fit as I'd like. Through high school and even my freshman year of college I was pretty fit, I exercised and worked out a lot regurarly. In the last year or more, I've dropped the ball. Less time, less motivation, and this summer even when I want to work out its not convenient. I have a horrible schedule to work around. I just started to do some stretches and simple exercises, either before bed or when I wake up, but I'm just getting into the habit. Wondering what you ladies do to keep fit around your hectic schedules, and what might help motivate you?