Because of word limits on our submissions for critique and monthly gaps between meetings many of our members start their submissions with a synopsis of what happened before this latest installment. It’s a big help especially for people who might have missed a meeting so didn’t get to read the previous part/chapter.
A writer doesn’t get that opportunity when their book goes out into the world though. If you have a series you can’t stop someone from starting at book three, or maybe your publication schedule means they wait a couple of years between book two and book three. Then your first chapters have to do this work – but without being info dumpy and boring, because some readers will be binge-reading your books all in a row and don’t need too thorough a re-cap.
It’s a fine line to walk, giving just enough information to remind the reader who this character is and what they did recently without carrying on about it too long. Think of books you’ve read that did it poorly, think of books that did it well. Reread them and analyse what the authors did and practice it in your own writing. Beta readers and critique groups will be happy to let you know if you under or over did it. As with nearly everything, practice makes perfect.