Follow the Primal Blueprint! There are so many tweaks within the program that can help but different specific approaches work best for different people. For me it's eat lots of veggies for volume but very little sweet fruit, focus on fairly low-calorie foods such as eggs, seafood, meat, green olives, avocados rather than lots of butter, oil, cheese, cream, bacon, nuts etc. And don't always keep chocolate in the house! Oh, and low-quality salt in foods such as cheese, nuts and olives seem to cause water retention for me.