Probably things you know, have previously thought, OR maybe don't know as you've never had a child before.
If that is the case here are the top 10 tips for traveling on a plane with a child offered by Archaeologous (tour specialists).
Tip #1: Try to time the feeding of your baby 'close' to take off or landing. The chewing/swallowing motion will help their ears to pop.
Tip #2: Always have your child on an inside seat, preferably between 2 responsible adults or by the window if it is just one adult. Never is the child to be on the aisle seat as there is too much activity of food/drink/duty free carts passing.
Tip #3: Tell your child to hold the hand rails as they enter the plane, and to keep seated after the plane lands as the overhead bags may have changed positions and could serious hurt a small child if they are in the aisle.
Tip #4: Always take turns staying awake if there are 2 adults traveling so that there is always one supervising adult with the child.
Tip #5: Try to bring along activity books or games that will use up some of the flying time.
Tip #6: Keep your children awake during take off and landing. Due the pressure change it's easier to keep up with opening the ears if they are awake.
Tip #7: Keep the child's seat belt or the infant's safety belt on at all times as turbulence can happen at any time without warning.
Tip #8: If your child has a medical condition that might arise during the flight, inform the flight attendant and counter agent before take off.
Tip #9: Keep your child supervised. It is not a good idea to let your child wander the aisle or the gallery where there is hot coffee etc. being made.
Tip #10: Show the child the map and really explain where he/she is and where the plane is going.
Other Helpful links: http://www.archaeologous.com/blog/163/tips-saving-money-athens-by-archaeologous/