Some great advice here already. I've flown many times with my 2 kids. At the age your baby is, here are my tips:
- Bring a bag that you can hang on your stroller...plan so things are as hands-free as possible. Have your ID and cash in an easy-to-reach place for being able to grab them quickly when you're checking in, going through security, and in any little airport stores.
- Use an umbrella stroller for the airport. Something light you can fold up with one hand (or ask another traveler in the security line to help while you hold the baby) - because you are required to pass the stroller through the security belt. Don't bring a bulky heavy one. You can use the stroller all the way to the gate...while you're waiting in the gate area to board, ask a gate agent to 'gate check' your stroller for you. Then you can stroll it all the way to the gate and they will return it right where you get off the plane.
- After you've gone through security, buy a bottle of water if you're going to need one to make formula...if you're nursing, then no worries....get the water for yourself. :) Don't assume you'll get anything quickly (or at all these days!) on the plane. Make sure you have any snacks you're going to need (those Gerber puffs if your baby is eating those yet, a banana, Baby Mum-Mums, and a few little snacks for you too).
- Before you get on the plane - go to the bathroom! The last thing you want to have to deal with on the plane is peeing in that tiny bathroom while holding a 7 month-old! Make sure to change the baby's diaper before you board too! Target also sells disposable changing mats...get the box that has the 10 count...they are big enough to cover the entire nasty changing tables in the airport!
- Get some of those scented plastic bags (Arm & Hammer makes them)...you can pick them up at Target in the baby section...they also have cute little dispensers for them...in the unlucky event of a poopy diaper or baby throw-up on the plane. Those bags are awesome because you can basically hide any smell with them, so other passengers won't have to smell anything. Be sure to bring a change of clothes for your baby...an outfit that folds up super small to maximize space in your bag.
- Personally I don't bring my baby's car seat (I either check it or rent one on the other side). I can't handle all of that bulk. Planes are tiny enough to begin with and managing a huge infant seat into that mess is something I wouldn't do.
- Bring a blanket ... something not too bulky. But perfect if the plane is too cold, baby falls asleep, anyway at some point you'll be happy you have it.
- If your child were older I'd also suggest bringing a portable DVD player, but I don't think that's necessary at this age. Do get a couple of brand-new fun toys and books. Make sure to encourage drinking something or using a pacifier during takeoff and as soon as the pilot announces the descent (that one is usually worse on ears).