It's pretty straightforward: you either click on their profile or (if you know someone's username@server via some other medium), search for them on your 'home' server and you'll see their profile. Then just click the 'follow' button.
Under the covers this sets up the federated follow relationship, but the UX feels the same as following someone on twitter.
There is one slightly more complicated scenario; if for some reason you're exploring a different server and find someone there you want to follow. In that case you still click the follow button but have to provide _your_ username@server string which triggers the necessary back-and-forth to get the follow relationship set up.
That makes sense, but my case is before I know who to follow. Is there any way to explore what’s going on on a server? Like browsing a news group on Usenet or checking a subreddit before subscribing?
> Like browsing a news group on Usenet or checking a subreddit before
How would you do that on Twitter? Follow the hashtags. Why do you insist on limiting it to a server? That's not really how it is supposed to work anyway, it's not those things you mentioned.
But how do I know what hashtags are there? I don't know what to follow is my issue. I need to bootstrap my set of followed things and people and how do I do that?
If you're not a part of some clique that decides to move off Twitter together, then I doubt you'll be able to just recreate a similar environment.
Otherwise for someone who posts frequently and has a good following, then it's probably worth it to start posting on Twitter and Mastodon at the same time, that's the only way it happens. Big movers and shakers are either going to stay on Twitter or drag everyone else with them, basically unlikely to happen.
Under the covers this sets up the federated follow relationship, but the UX feels the same as following someone on twitter.
There is one slightly more complicated scenario; if for some reason you're exploring a different server and find someone there you want to follow. In that case you still click the follow button but have to provide _your_ username@server string which triggers the necessary back-and-forth to get the follow relationship set up.