Goal No. 1: Plan Your Daily Food
First, take note of every bite of food you have during the day. Don't forget that run through the supermarket - all those tasty samples you couldn't pass up. "A food journal is the single best thing you can do," says Gary Foster, PhD, clinical director of the weight and eating disorders program at the University of Pennsylvania School of Medicine. "You become more conscious of what you're doing. It helps you monitor yourself, and make corrections in mid-course."

Dietitians call it a food journal. But really, it's research for your plan of action, he explains. You'll see where you need improvement. "Plans work better than platitudes," Foster tells WebMD. "Instead of 'I'll exercise more,' make it 'I'll walk tomorrow morning at 7 a.m.'"

Keep it simple. Journals don't have to be labor-intensive, he says. Focus on your high-risk time slots when you're most likely to get off course. Example: You know you eat junk at night, or that you snack after 3 p.m., or between lunch and dinner. Just keep notes during that time period. You'll quickly see problem habits: banana split vs. banana, the whole container of nuts vs. a handful.

Set specific goals. You can't just tell yourself to eat less junk food after 8 p.m. Be specific - 'I'm going to substitute popcorn for potato chips.' That way you know exactly what to do. There's no question.

Use weekends wisely. "When things are a little quieter on weekends, you can think about the upcoming week," says Stokes. "Decide what you're going to eat. Go to the market, so you're a little ahead of the game. You can even prepare food on the weekend and freeze it, then pull it out during the week."

Consider your options. Keep lists of healthy foods and meals you love, and plan accordingly, adds Elisabetta Politi, RD, MPH, nutrition manager at the Duke Diet & Fitness Center at Duke University Medical School. "I advise people to think of five different breakfast, lunch, and dinner options. Then you'll have some freedom - you can choose from your favorites. But your eating will be more structured. That's what's important."

Shop wisely. A well-stocked fridge and pantry can make it easier to grab a healthy snack or prepare delicious meals that are also good for you. Keep basics like these on hand: low-fat milk and yogurt, eggs, peanut butter, a variety of fresh fruits (include berries and grapes) and vegetables (include carrots and celery), soybeans, garlic, whole grain pasta/bread, fish, and high-fiber cereal.

Plan healthy treats. Low-fat cheese or yogurt, hummus with veggies, and fresh fruit are great choices. Keep them at home; take them to the office. That will help you eat the right foods when you're starving - especially in the late afternoon, during drive time -- and when you finally get home at night.

Do it yourself. These are great prepare-ahead healthy meals that will keep you feeling full and help you control your weight:
 

• Make a dried-fruit-and-nut mix for emergency snacking. (Be wary of granola, since it typically has lots of sugar, says Stokes.) Pack small amounts in a little plastic bag - great for the car or office. 
• Cook a big pot of homemade vegetable soup, which can be frozen for several lunches or dinners. 
• Try smoothies - blend low-fat yogurt and fruit - for a grab-and-go meal. 
• Mix up big salads or a pasta primavera with lots of veggies and whole-wheat pasta. Prepare large quantities so you can have a moderate-sized helping for dinner and then have leftovers for lunch the next day. 
• Buy healthy frozen entrées. "These have really improved," says Rolls. "They have more whole grains in them now, and they seem to be getting tastier. If I'm traveling and can't get to the grocery store, I make sure I have frozen entrees on hand."

Don't limit yourself. It's OK to eat breakfast food for snacks, lunch, or dinner. "You can eat a hard-boiled egg or cereal any time, not just breakfast," Stokes advises.