You will have such a great time! (at least I hope you will)
Looking back on it, travelling with DS was such a treat when he was still so little.
We wore him in the airport and while on vacay and never missed taking a stroller.
I would take one change of clothing for me and DH and two sets for DS, packing all into ziploc bags and forcing all the air out. This method takes up very little room in the carry on. Same method works for diapers. We never needed the extra clothing but I liked knowing it was there.
I am a planner so I would take a little cooler with enough snacks and water for me and DS. I was still breast feeding at the time and DS was into finger foods. Regulations may have changed but I never had a problem taking liquids through TSA.
Our experience on the plane was always great, the FAs seem to love having a baby in their section. Only once did I witness bad behavior. A family across the way from us asked for water for their child and the FA was a total bit@h about it and wouldn't give them water prior to take off.
Get to the airport plenty early so no one feels rushed. Common sense stuff like checking/doing diaper changes prior to boarding, keep your stuff to a minimum, combine your purse into the diaperbag, stuff like that.
Oh, one more thing that saved our sanity - assign duties and stick with the plan.
For example, one parent takes the baby thru security, the other is responsible for the bags/carseat. Agree on this ahead of time so you aren't standing there saying "who's got what? where is X?" and so on because as soon as you get stuff loaded on the belt, it actually moves pretty fast.
In our family, DH would take DS in thru first and I kept track of the carseat and carry-ons. DH knew his job, I knew mine and neither of us worried about the other.