1. Take it one step at a time
Start by paying attention to what you eat. Cut back on fat and sweets and add more fruit and vegetables. After you have that under control, add exercise. If you hate to exercise try it for only 15 minutes a day at first, then a 1/2-hour. Keep in mind that while you are exercising you are burning calories and not eating. Also, it will be easier if you chose an activity that you enjoy.
2. Find a friend
It is always good to have support when you are trying to lose weight. Find a friend who wants to lose weight and compare notes, weigh-in together and maybe even have a contest.
3. Use weights
Working out weights will build muscle and raise your metabolism so you will burn more calories. Also, muscle takes up less space than fat so you will be smaller ( but probably weigh more).