First time air travel?

what size should a carry on luggage be?? I am traveling with a child also so any tips/ideas appreciated.....

hand luggage is the size of a small bag, but it depends who you're flying with so you should check on the airlines webby. also you normally cant take any liquids through checkin with you now but can buy drinks etc in the terminal building.

if its a long flight i would take one of those magnetic travel board games so you can play it with your kid to keep him amused. also take some boiled sweets to help stop his ears popping when taking off and especially landing.