Try to eat a quantity similar to your regular meal that you would
measure, weigh etc. Take the rest home. It is not rocket surgery.

i

What I usually do is try to pick items that I'll know the calorie content
of.  For instance, I'll choose a grilled chicken breast because I can easily
find the nutrition info on that either in my book or on the web.  Load up on
veggies without the cream sauces and you'll know that no matter how much you
eat of them (except for potatoe, corn and carrots) you won't be adding much
to your daily total.  Fill up with a salad, dressing on the side and dip
your fork into the dressing to get the flavour.  Also, ask if they have any
fat free dressings.  Skip the breads and biscuits as well as extras such as
mayo.  And as always.. take half of it home.  Remember, just because it's on
your plate does not mean you have to eat it.  Keep common sense and your own
knowledge of what's right and you'll most likely come out fine.