Voting, commenting, sharing content and news articles in relevant communities nearly ever day. Reporting spam. So basically, just actively participating.
I'm still using reddit (desktop only) until they shut down old.reddit. That's been my line in the sand ever since the redesign was launched. So whenever possible I do my best to recommend lemmy and/or explain how it works to anyone interested because I think Lemmy would appeal to most redditors. The problem is the average person has it in their head that the fediverse is a lot more complicated than it actually is. Everything can be learned as you go. Which is exactly how I learned the ropes on reddit 12 years ago. But since so many people insist on having their hand held I'll jump in to help out when I can.
For Android users, recommend Boost (which just launched). It used to be a Reddit client, then the dev made it for Lemmy. I did try to get into Lemmy without a solid app, but couldn't do it. Boost changed that for me. Now Lemmy is as smooth as Reddit was. Recommending an app that makes it as easy as Reddit might help for some people like it did me. :)