You already got some good advice in the previous post.
I would also add that if you know ahead of time that you'll be going out, you can plan for it accordingly. You can save some calories from your other meals and then use more at the meal out. You can also make sure to get in some extra exercise on a day like that.
I know some people have to do a lot of dining out because of their job situations. But I also try to cook as much for myself as I can, leaving dining out as an only-sometimes event to look forward to.
Even if the restaurant you visit does not have a nutrition sheet (as JAMBABYO suggested) you can look up similar foods at chain restaurants and get a ball-park for how many calories might be in the dish.
Don't feel awkward about asking questions about how the foods are cooked. You're the consumer and as long as you ask respectfully, most restaurants are happy to give you information/happy to keep your business in the future!