I used to try and count the carbs and then give my daughter her shot BUT then she wouldn't eat everything we counted, so i started with 1/2 the amount we believed she would eat and when she finished give the remaining based on actual carbs and if she would be exercising just after we ate. The pump made this so much easier with a bolus, but first she had to learn to count carbs and bolus WHEN she ate.

i ALWAYS have insuline, meter and snacks on hand. so if i stop to eat i take it when starting to eat.

That depends on several things. 1st - what type of Insulin are you using? Fast acting, like Lyumjev, start working in @15 mins., while short acting insulins like Humalog take 20 - 30 minutes to start working. So, taking your insulin before you go out could cause a low bg. 2nd - where are you going? Fast food, you'll be served quickly. A fancy restaurant, your food could take 45 minutes to be prepared. Mealtime insulins will have already started, resulting in a low. 3rd - how far will you be traveling? Driving an hour from home, or even a half hour, is too long to take your insulin before you leave, for the same reasons listed above.