I used The Biggest Loser cookbooks as a guide in my recent weight loss (45 lbs since March). At the beginning of each cookbook, it basically gives you a little rundown of what needs to be in your diet every day and what doesn’t.
Here’s what I did:
Replace any flour products (breads, pastas, cereals, tortillas, etc.) with whole wheat. Complex carbs fill you up longer and give you more sustained energy.
Avoid refined sugar as much as possible. Check the nutrition labels-- anything over 10g sugars per serving is too much.
Multiply your current weight by 7. That’s how many calories you can have per day. Yes, it’s a lot less than you thought. It’s doable. You’ll learn to eat lower calorie foods that fill you up.
Count calories religiously. I only did this for the first two months, until I had basically memorized the calorie content of all the foods I eat often, but I lost 25 lbs doing it. I kept a food journal and that helped a lot, both in education and in keeping me motivated.
Follow a modified food pyramid of 4-3-2-1: 4 servings fruit/veg, 3 lean protein, 2 whole grains, and 1 “extra” (~200 calories) per day. If something you’re eating falls outside that structure, seriously reconsider eating it.
Eat 4-5x a day in small amounts. I ate breakfast, morning snack, lunch, afternoon snack, and then dinner.
Do not eat out. Seriously, just avoid it as much as possible. It’s so difficult to find anything healthy, and even if you do find something low-calorie, it will still be full of sodium, which will impede your weight loss. I did it enough to keep myself sane (probably once a week), and only at places that provided nutritional info. I also limited myself to half servings. If you do it that way, you’ll lose your enchantment with it, because you’ll find it’s much more of a hassle to find something that fits into your diet than it is to simply cook a meal at home.
Work out a lot. I worked out daily and still do. 30 minutes cardio (run/walk), 30 minutes weights, alternating upper body, lower body, and abs/back. Don’t stress the same muscle group two days in a row-- exercising tears down the muscle, and you need at least one day to rebuild it.
Learn to cook. Buy healthy cookbooks-- I highly recommend The Biggest Loser series; the food does not taste like diet food and is easy to prepare, even for someone like me who hates cooking.
Read nutrition labels. Not just the nutritional breakdown, but also the ingredients. Stay away from white flour, sugar, high fructose corn syrup, butter, eggs, and most oils. (If you must have/use oil, go with olive oil.)
This one helped me a lot: find low-guilt desserts. I’m a dessert fiend. I go through probably 5-6 no sugar added fudgesicles (60 calories each) per week. I’m also a big fan of Blue Bell’s No Sugar Added ice cream (in small amounts!) and Jello’s 60-calorie sugar free dark chocolate pudding cups. TBL also has a lot of easy dessert recipes.
Good luck, and stay motivated!