
Start with audience and task
Write down who needs to find you and your task: receive updates, publish work, organise a group or ask a question. Find people already present and usable formats. A huge theoretical audience does not answer the question of your actual contacts.
Compare operating effort
Effort includes writing, review, replies, moderation and account maintenance. Try one scenario with non-sensitive content. Observe access, understanding and responses rather than creating many accounts. Define when to review the choice and how to keep useful content.
Your reading path
Useful comparisons
Profiles to explore options
These links offer relevant leads for this topic; they are not a ranking or universal recommendation.