Building Up Smaller Traditions
The best traditions begin small.
They are things members, perhaps just 2 to 3, were doing anyway.
Over time they become convention. More people join in.
Soon they are accepted and adopted by the entire group.
If you're looking to start traditions in any group, look to see what people are already doing and highlight it in your content posts, newsletters, and more.
Help make it a regular occurence. Gradually promote it.