You do not have to be on all the types of social media. Pick your favorite one(s). Your posts should not be only about your book. The goal of social media is to be social, to connect with others of shared interests especially related to your book genre, subjects, and themes, and thus attract interest in your books.
Penny Sansevieri, of Author Marketing Experts, offers tips and suggestions in this article on IndieReader:
12 Things to Know About Book Marketing and Social Media