Our flight went well. Both kids made it through the flights with no meltdowns.

Countdown began long before we left for Disney.

Getting prepared was the biggest thing. I planned on checking car seat and suit case. The stroller went in one of the traveling cars. I had one carry on, plus porter of course, my diaper bag/pump bag. I filled it with the following:
Pacifiers 3 extras
Pacifier clip
Finger foods
Sippy cup
One full bottle
Four smaller bottles filled with milk in cooler bag(yes you can carry on breast milk)
Throw away bib
Diapers and wipes
Few toys and a book
Taggie blanket (small)
Pump
Baby food
My bag is definitely full! Could not fit one more thing in it.
When we got to the airport I had porter in the baby Bjorne or carrier/wrap. I checked in and checked our luggage. When I went through security it was like they saw us coming they opened a line just for us. I did have to take out all the liquids and gels, and they had to inspect my breast milk. Lol! But it went very well. The hardest thing was using the bathroom. Trying to go with a baby on my belly and a backpack on my back was difficult to say the least.
While waiting to board I allowed porter to crawl around and play before he had to be contained for an hour and a half. We were allowed to preboard which was nice but was almost too much time. I wouldn't have done it the other way though, too many people trying to get on at once.
Everyone was boarding and porter just played. We were very lucky to have an empty seat next to us. Just in case....
Ready for takeoff porter drank his milk then he slept. After about an hour he woke up and we played, read a book, looked out the window, and ate snacks.