From a helpful Spinster @Maat
spinster.xyz/home
I'll post more tips as they become available for anyone who wants to dip a toe in the water.
"I'm sure your members will be fine creating a profile as presumably they did so on Mumsnet. You then go to your home page and click on the 'Spinster' tab at the top. That takes you to the feed for all of us. You can click to follow people (I suspect Mumsnet has this facility too so, again, assume members will find this easy enough). The icons under each post allow you to 'reply', 'share post' and 'like post' in that order. I'm not sure about Mumsnet but, unlike with Twitter, sharing a post doesn't give you the opportunity to share it with a comment of your own.
Once you're following people the tabs at the top of your home page make more sense. 'Home' is for people you're following, 'Spinster' is for everyone on our part of the Fediverse and 'Fediverse' itself is an open forum where you get all sorts of people and different groups, not all of them women-friendly.
Good luck. I'm sure the members will be fine. I can't imagine Spinster being more complicated than Mumsnet."