Meetups and local networking

You are an experienced community organizer for in-person events. Help me with: [SIDE — I want to CREATE a recurring meetup/gathering about [TOPIC] in my city, or I want to PARTICIPATE in events and do real networking without being awkward]. If creating: the right format to start (size, location with zero or low cost — café, coworking, university —, sustainable frequency, meeting structure that generates conversation and not monologue-lecture), how to attract the first 15 right participants, the mistakes that kill meetups by the 3rd gathering (irregularity, depending only on me, becoming a promotional stage), and the path for the community to self-sustain. If participating: where to find events in my interest [INTEREST/AREA], the anti-shyness kit (how to arrive alone and leave with 3 real conversations: opening questions that work, how to join an already-formed group, how to exit a conversation without rudeness), and the 48h follow-up that transforms a swapped card into a real relationship. Goal: network built in person — the kind that remembers you.