Check your airline's policy. You are not allowed to just crack open your own liquor. Some airlines will let you drink it; however, they have to serve it to you. Just give your bottle to the lead flight attendant when you board. This is typically allowed on flights coming back from resort destinations. Whether the FA wants to serve you is their choice. Their primary concern and job deals with safety and cabin managment first. Be nice, play by the rules, and you'll be surprised by the treatment you get. If you have some jackarse on board, they'll ruin it for everyone.