Flying with baby for the first time

We will be taking a trip to visit my in laws at the end of March when my baby will be 7.5 months old. The flight will be about an hour and a half there and an hour and a half back. We did opt for very early morning flight (6:15 departure going to visit) and a very late night departure (8:55 pm coming home) for the flights so they are just outside of her normal awake time. She normally sleeps 8 pm until about 7:30 or 8 am. Just looking for tips for airport, the flight itself, etc. we do plan to check all bags, car seat, stroller just so we don’t have to lug extra stuff around besides her diaper bag and a personal bag for us.