Weigh and calculate for my first different meal at home.. Yes, even salad!! Then stick to the 8 olives (now), 1 avocado, 1/2 pepper, 10 slices cucumber etc.
Restaurants I try to go online first before going out and seeing their menu's and pre guestimate before going. Then I decide whether my guestimation is right according to the food when I see it.
Friends tend nowadays to come to us for meals or will do more buffet style, help yourself and we take some food with us to share. It means that I can have food that keeps my stomach working but allows them to also share some food that they may not have tried before.