I find that the location is an important aspect for social meetups. It should be comfy and facilitate a conversation with multiple people. Additionally, you just need a seed of people that can’t stop talking about Bitcoin of which at least a couple actually follow recent development.

For the technical meetups, it helps to have a good mix of novice friendly topics, bike-shedding topics that everyone can weigh in on, and a few topics to pique the interest of experts. Also, have a guest or two to build some momentum! We have a few suggestions on running a Great Socratic Seminar on the BitDevs blog. You may find it interesting.