To start, you should choose an instance that had been around for a while and isn't too small. Instances do shutdown occasionally but the admin(s) will give you

To start, you should choose an instance that had been around for a while and isn't too small. Instances do shutdown occasionally but the admin(s) will give you plenty of time to migrate to a new instance. Mastodon has built-in tools to migrate your whole account (and content) to another instance if needed. I'm currently having to do that because a large well-established instance (mastodon.technology) is shutting down the end of the year.