First, ask yourself whether you've set a goal weight that's too low -- your body may be telling you that the weight would be hard to maintain. "If you're sure you need to keep losing, remember that the final 5 pounds are very different from the first," says Madelyn Fernstrom, PhD, director of the University of Pittsburgh Medical Center's Weight Management Center. The more weight you drop, the fewer calories your body needs -- so it becomes harder to create the deficit required to slim down. Aim to shed 2 pounds a month (instead of per week, like you did when you had more to lose) by burning 250 more calories than you consume every day. Here's how: Shave 100 to 150 calories off your daily diet (skip your nightly glass of wine, for example) while you also burn an extra 100 to 150 calories (jog for 10 minutes more or take three 10-minute walks throughout the day).