Anyone have tips for traveling with a child under one?🤗

My husband & I will be flying with our 6 month old son down to California this spring/summer(approx. 1.5-2hr flight) I don’t know what to do for his sleeping situation or what to bring with me for the flight that won’t take up too much space. 😶😶 complete newbie to flying with a baby so any and all advice will be much appreciated. ‼️