How to be Insulting at Christmas: Refuse to give any guests a drink, on the grounds that it's for their own good not to drink and drive. Have plenty of soft drinks to offer them though. Then pour yourself a large Scotch, on the grounds that you aren't going anywhere and don't have to worry.
How to be Insulting on the Beach: Sit by the water with a fishing rod, and throw revolting lumps of old bread into the water where the children are enjoying themselves.
How to be Insulting Abroad: Ask for local delicacies and leave them on your plate.
How to be Insulting in the Street: Wave frantically across the street to people who are trying to ignore you and try to attract as much attention to them as you can.
How to be Insulting in Banks: Take a tape recorder with you to the meeting with the manager. Say nothing the entire time, but simply record all he says to you. Then when he's finished play it back to him at twice the speed and leave.