The answer to this is different everyday.
Some of my common ones are: post lots of notes, reply heavy, reply thoughtfully, zap hard, wear nostr gear, annoy irls with nostr talk, report bugs, make suggestions, try new stuff, or attempt to learn a skill that could help the cause.
Some more obscure stuff I've done: change the colors of the 'open' sign at my shop to purple & orange, planted purple & orange carrots, mailed shwag to plebs. 
Most importantly though: show up 😊

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