1. Gossip privately about the dry-as-sand turkey my grandmother makes, because she's too scared of germs to make a properly juicy turkey.
2. Listen patiently while hypochondriac relatives bemoan their always-impending-but-never-arriving doom.
3. Yell across the kitchen about whether or not the gravy "needs sieved." Meanwhile, gravy burns and no one gets any.
4. Roll eyes at the gifts they don't like and complain about people being cheap/lazy. Seriously, I get them all honorary charity donations because of this.
5. Make snide comments about others' sartorial choices, then somehow relate this to genetics, as in, "Melissa's got on quite a...uh...a
feminine blouse on there, I'm sure she gets her bosom from YOUR side."
6. Threaten to paddle the children, no matter what they are doing.
7. Ask every female in the room, regardless of age or marital status, if she is pregnant yet, then demand to know why not. Bonus points for throwing a "respect your elders young lady" fit when told, "none of your business."
8. At least one uncle must get drunk and tell dirty jokes. Again, there are bonus points for having young children in earshot and able to repeat the jokes for the edification of their 4th grade class. One uncle, an artist, prefers to draw pictures in his sketchbook of naked ladies and show them to everyone.
9. Loud Argument: This can be over politics, religion, sports, who showed up or did not show up, who helped set up the folding chairs (an astonishing two-hour long rant came from that), who is a Bad Woman (this can take many forms: bad wife, bad mother, bad daughter, bad sister, but men in my family are reckoned above reproach).
10. This year, we have a new addition: My grandparents moved to a nursing home, which somehow my grandmother interprets to mean that she does not have to actually dress herself at any time or for any reason, despite being perfectly capable of doing so at any time, without assistance--such as in the event that you offer to take her shopping. Now, the new tradition is taking bets on whether or not she will be naked or simply in her undies when she answers the apartment door, and drawing straws for who has to bully her into the bathroom and make her get dressed. My aunt Polly lost the last bet.
Feel free to adapt any of these for your own use.