Depends of the topic
- if there’s an active community on that topic, better to contribute there
- if there’s no active community but an inactive community with a lot of subscribers, you can try to revive it
- there might also be an adjacent community that is already active, and your topic is niche
I see you mentioned tech, there are quite a few communities on programming.dev and lemmy.zip
Feel free to crosspost to !fedigrow@lemm.ee , it’s a community dedicated to community growth
Feel free to crosspost to !homeimprovement@lemmy.world for additional advice