I think that blinking an LED is already too much, and programming a badge is too much work while listening to amazing talks anyways. Hope you brought a pen!
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I'm using Comic Sans MS, pray that I don't alter it again.
With the help of a wonderful friend the ~90ish red/green/blue simple add-on kits are all now packed! It's fairly simple to solder, definitely beginner friendly!
For the event I had ordered 3 boards each in green, red and blue. The blue version has the order number on the front. All of them only have one of the LEDs correctly connected, for the other three you have to botch a bit. But 1 LED seems plenty strong already anyways.
The connector can probably be SMD as well, as it wouldn't hold as much stuff anyways. Stickers on shirts might work the first day, but this is a three days event. Supercon can be overwhelming, so taking time to program a name tag might already be too much. There could be some slightly glowing white LEDs instead, like @arturo182 uses in his marker badges that he gave out at chaos camp. But then this badge might need some stacked boards instead. So white silkscreen feels like keeping it simple.
Upvoted just for the Papyrus lulz