@BillAlexander I've only been here a month, so for what it's worth...
Start posting, preferably a cat, any cat will do. Borrow your neighbour's if necessary or steal one from the internet.
Boost and follow other people you like.
Some say you should fill out a profile. I don't tbhink that's so important. It's the content that matters to me. Did I mention cats? A really nice cat so people know you're a good person, though a good dog will do at a pinch.
Anyway, welcome and enjoy yourself here.