If I had to give one piece of advice to someone who wanted to lose weight, it would be to journal your food. It doesn't matter if you count calories, points, or exchanges, just keep track. When I track calories, I lose weight. When I don't track, I don't lose.
When I don't track, I slip in extra snacks, "just one more bite," or another cookie. It's much easier to eat an extra few hundred calories a day if I'm not aware of each bite. It's easier to say, "It doesn't matter." or "I'll be good tomorrow."
There have been studies that show that this plus not skipping meals and eating out less can improve weight loss results.