Set the rules
First of all, you need to set the rules before you leave the house. You need to sit down with the children and clearly tell them how they should and should not behave during the outing. Another important thing you need to do is let the kids know about the consequences of bad behaviour, so that they remain quiet and well-behaved throughout the outing.
Pick the right restaurant
Another important thing that you need to take care of is to choose the right place to dine out. Make sure you do not go to a place which is formal, as the management and the gathering there would certainly not appreciate any inappropriate behaviour from your children. Instead, visit a place that is popular among children. A good fast food chain would be a better idea as it will be more suitable for your kids.
Be there in time
Reaching on time is also very important; if you get there late, only to find out that the restaurant has run out of your kids' favourite foods, they will not be happy. To avoid this, reach the place where you want to dine on time, so that you have enough time, and can order the food of your choice.
Motivate the children
Another good way to avoid any problems while dining out is to motivate the children to finish their food in time. You can promise a reward for them if they behave properly; for example, promise the kids ice cream if they eat their food nicely.