Know where overnight accommodations are located. When flying, schedule non-stop flights with younger children. In the event you must change planes, allow one hour between connections. Don't crowd the back seat of you auto with luggage. Leave ample room for rear seat passengers.
Airlines allow one carry-on bag per passenger.
Remember what you carry on, you much carry off and lug from one terminal to another. Bring entertainment . Give each child a choice of games, books, activity booklets that they would like to bring. Pack these separately and within each reach. Include some surprises that you picked and keep them out of sight.