How can I stay in shape with a broken toe?

No impact. When you injure the foot, it can be hard to not want to work out. As a patient under someone's care for a broken toe, i would hesitate to advise you to exercise at this time. However, upper body workouts are ok, swimming is ok and so is pilates/yoga. Restrictions are those that directly affect the foot involved, and absolutely no impact exercises period. No treadmill or elliptical.
Several things. Do upper body exercise you can do exercise for the lower body also just not running, eliptical or any thing that puts pressure on the toe.
Swim. And concentrate on upper body excercises.