Flying with baby

We are flying with our 6week old next week for the first time and I'm very nervous. We have two one hour flights and an hour layover in between so it shouldn't be too bad, but any advice is much appreciated! Also, how do we prepare bottles? I'm in the process of weaning so I'm not sure I'll have enough milk for the trip and would like to have bottles with formula ready to go. Do they allow for that at security? Thanks!