You and you alone hold the power to keep yourself on track. When you're out for dim sum, see if you can get some of the stuff steamed with sauce on the side, hold the rice. Street fair -- don't eat anything there, because it's usually pretty empty-calorie HIGH-calorie stuff. And as for the ice cream, there's usually a low fat option, and get a single or kid's size. I hope I helped
I'm actually going out myself with a friend this afternoon. Anywhere we go in my town, there's an option to screw up, but there are also other options to take to NOT screw up. If you want something, guesstimate the calorie count and see if you can work it in. If not, you can probably make something similar at home with a fraction of the calories!
IE: Caramel Apples vs. Baked apple (no toppings) with cinnamon and a sprinkle of brown sugar.