The trick for traveling with young kids is to plan, plan, plan.
The first thing, if possible, travel in the morning. All kids are happier in the morning. You don't want to set yourself up for failure by traveling in the afternoon, when you know they are going to be cranky. For infants, a sling is a great for traveling. You want to make sure you have a bottle, a breast, or a pacifier to soothe those sore ears during take off and landing, if you are flying.
Another great trick I was taught, was to wrap small toys in tissue paper, so that your kids can have a lot of fun opening them and playing with them. As well as, individually packed snacks. You cannot rely on an airline or airport to feed your kids, and you have to expect delays.
Since sleep is absolutely King in our house, it might sound crazy, but we travel with black trash bags, blue painters tape, and a white noise machine to create an amazing sleep environment for our kids. So that they are in a dark room, without any interruptions. Then we are happy travelers.