My "Getting Started on Mastodon" tip is to follow a ton of people.
Follow the people you followed on Twitter, sure, but especially follow new people you didn't know on Twitter. Follow people who follow you. Check out the local or federated timelines and pick random people to follow.
You can remove them later if you don't like their vibe or once you get a sense for how you want to use Mastodon, but in the meantime it's much more interesting to have a bunch of new posts whenever you come visit.