Start with eating 5-6 small meals per day instead of the 3 square that you learned you should eat when you were little.
This helps speed up your metabolism and gives your body a constant supply of energy. If your body has energy there is no need for it to convert calories to fat. I'm not sure how much you are eating already, but try to stay around 1400 - 1600 calories a day.
My meals are usually as follows:
Breakfast = two toaster pancakes with light syrup and one fried egg (dry not fried in butter or fat). This is a good balance of carbs which your body uses for quick energy and protein which is used a bit slower.
mid morning snack = one granola bar (around 140 calories) and either some fruit or some nuts (almonds or macadamia are my favorite).
Lunch = Turkey or Ham sandwich with mustard, cheese, lettuce and tomato. Occasionally I'll also have a small serving of tortilla chips and salsa as well.
Mid day snack = sometimes another sandwich. sometimes chips and salsa with some fresh fruit. sometimes a salad with lowfat dressing.
Dinner = grilled chicken breast (BBQ sauce optional) steamed corn and a dinner roll or peice of bread.
You can change the foods you eat but try to get a good balance of carbs and proteins. Be sure to get good amounts of fresh fruit and vegetables as well as whole grain breads and lowfat meats such as turkey and chicken. Ground turkey makes delicious hamburgers without the fat in ground beef.
Just try to keep each meal to around 300 - 400 calories and make smart decisions about what you eat. No more fast food (although Subway makes delicious low calorie sandwiches) or junk food. it is ok to treat yourself once in awhile and if you shop around you can find delicious lowfat and low calorie alternatives. Snackwells makes delicious cookie cakes that are only 50 calories each. I'll treat myself to one or two every once in awhile. There are also lowfat ice cream sandwiches that are barley over 100 calories that really take the edge off of junk food cravings. just remeber "All things in moderation."
The most important thing you can do besides eating right is moving more. If you can't get to a gym, start taking walks with a friend. Take the stairs instead of using the elevator. Do push-ups, squats, and cruches (NOT FULL SIT-UPS) to help build muscle. Cardio is great for your heart and for calorie burning. Ride a bike, go for a run, roller blade... whatever gets your heart going.
If you want some more support check out this thread:
There is a group of us try to cut 10 pounds and we report in and give each other support. By the way... Welcome to A2K.