I unfollow (in contrast to unfriending) people who post things that I'm not interested in. I "hard follow" friends that post really cool stuff. By "hard following" I mean "See First" functionality of the the Newsfeed algorithm. It helps to keep my newsfeed more or less under control. I also try to teach the newsfeed to only show relevant ads by hiding those that I don't care about and clicking the ones I find interesting.