1. Step on a scale
   Weigh yourself after overindulging and you'll see that you haven't gained 5 pounds overnight.



2. Ask a friend for help
   If you've pinpointed a weakness, talk it out with someone you trust. If need be, ask them to gently call you on it the next time they see you putting yourself in a similar situation.



3. Walk more
   Even if you can squeeze in only 15 minutes, being active will remind you how good it feels to be fit.



4. Restart your food diary
   Maybe by this time in the plan you've been a little lax about keeping track, so vow to record every bite.



5. Set a new goal
   Sometimes boredom throws us off. Take a cooking class or try a new activity so you feel more enthusiastic about healthy habits.

Pick up Shape's special Make Over Your Body issue for complete details about this 21-day plan. On newsstands now!