Whatever works for you. lemmy.world is the big dog so there's a tonne of activity here but it can be a little slow at times and the target of malicious attacks. You will also find that the front page can be a real fire hose of content.

If you look around you can find regional instances that serve up a more local slant on things or a topic specific instance that looks technology, books, etc. Or you want somewhere more aligned with your politics or an instance with more porn.

There's something for everyone and no one-size-fits-all answer to your question.

I'm not sure I've made 3 accounts and I've had issues with 2 of them going down completely so far. The account that has yet to let me down is this lemm.ee one but I suspect its probably a matter of time.

I'd suggest signing up to a couple of instances you can use a program called Lasim to sync communities and blocks between them.

Honestly I'd just pick the instances that appeal most to you, karma's not a thing here so nothing is lost switching really.

It depends.

One which has communities on that you like will make your "local" feed more relevant. (have a look at !specialized_instances@kbin.social)

One which has a domain you like might appeal.

Otherwise, given you can subscribe to anything on any instance, it doesn't really matter.

Lemmy.world is awesome but the servers are overloaded and things don't load sometimes. Lemmy.ml is the next largest instance and seems to be a bit more stable but tradeoff is slightly less users. It depends on your personality too, if you are a super political activist you will probably want to join a political based instance matching roughly your alignment. If you're a sports but there are sports instances. There are over 1000 Lemmy instances each with their own goals and community. Keep in mind not all instances automatically federate with all other instances, they have to cross interact manually by users once for two instances to 'know' about eachother. So the larger all purpose instances like world and ml will have a much more diverse 'all' feed. Also some instances are defederated by most of lemmyverse due to allowing hateful toxic user behavior and inappropriate content

lemm.ee has been great

Search: bigger instances. Speed: something close to you. Bigger: juicier targets for DDOS, hacks. Smaller: likelier to disappear.

Check out different parameters on: https://lemmy.fediverse.observer/

personally i'd find a smaller one just for the sake of stability. there's a few fandom themed ones that are cool, plus you can subscribe to communities hosted on other instances no problem

Pick something close to you so you get low latency :)

If you’re super into right wing echo chambers then exploding-heads.com is for you. Probably Lemmy.world if you’re more center or left leaning.