Summarize:

If you lose too much weight at once, you might have more excess skin than you would if you lost weight slowly. Aim to lose no more than 12 pounds (0.450.91kg) per week. To lose 1 pound a week, you must burn 3,500 calories a week. You can reach this goal by cutting out 500 calories from your diet every day. This is a healthy range of body fat. Keeping a little bit of fat on the body will help plump up any skin left over from weight loss. Visit a doctor or personal trainer to learn your body fat percentage. Building muscle will also improve your chances of losing more weight. To build muscle most efficiently, you can either do fewer reps with heavier weights or more reps with lighter weights. Good weight lifting moves include deadlifts, bench presses, and bicep curls. Body weight exercises can also be useful. You can do crunches, leg lifts, and flutter kicks.
Lose weight slowly. Keep your total body fat between 14-22%. Build muscle to fill out skin.