So, compared to a badge that are handed out at an in-person event, this will require a little bit of effort ahead of time. If you want to have a badge for the event, you will need to send if for production fairly soon.
This years color theme matches OSHParks purple PCBs very nicely, and the fine silkscreen details will come out great, as they use a high DPI printing technique.
The KiCad project includes a badge design with a grid of regular 0.1" spaced pads, but the idea is that you remove all those and add in some circuitry that you think would be cool to have on your badge. And with the current state of silicon parts supply, probably something you already have or at least have found in stock somewhere.
This is ment to to be a fun little extra thing, so no need to spend too long on doing the perfect design, but maybe try to remix something you did previously, or experiment with that little part that you never got to use and is just sitting there on the shelf.
The important part is having fun and sharing with each other.