Not drinking soda anymore should help a lot on its own! I had to give it up last year for medical purposes, and I've lost (and keep off) about 5 pounds due to that. Doesnt sound like much, but it makes a difference!
Drink lots of water- a lot of time when you think you're hungry, its actually mild dehydration. Who knew?
Also, not eating red meat does wonders for me. Try to find something low-fat to snack on, because feeling hungry all the time is no fun at all! I love animal crackers (especially with some kind of fruity yogurt), and soynuts (hickory smoked are the best!). If your grocery store has an organic/healthy section, you might be able to find some really good snacks you've never seen before (Maple vanilla pumpkin seeds are better than candy, I say!

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Usually when I'm at wdw, I walk around so much that I can eat whatever I want to there, and still lose weight. I dont think I could ever be on a "diet" on vacation! The strawberry Minnie bars have no fat and only like 100 calories, btw, and those are great!
Good luck with your goal!