For Mastodon?
I use it the same as my Twitter, mainly googling mastodon lists of know profiles there, the I copy/paste in the search and follow them.
On Lemmy it’s easier, just do a search for the communities you’d like to join, for example:
Gaming at beehaw.org is amazing. Subscribe to that if you didn’t already.
The new design is indeed amazing.
But is it just me, or did they indeed removed lists, can’t find a way to add to a list or follow a hashtag, neither see or edit my lists in the new version.