I follow anyone that interests me with either their post, their comment and even a few times their username. Then I work backwards from there. If they start posting things I don't like then I unfollow them. It's not the ideal way to do it, that's for sure. I follow the maximum number of people and as new people filter in and I want to follow them, I have to unfollow someone else. It's getting harder to do though, because I increasingly recognize all of the people I'm following from a past conversation etc.
mk follows only a few people and I know for a time being kleinbl00 followed nobody and was only following tags and using the global posts. We are still a small enough community that this can work and you really won't miss much but as we grow, and we are growing, that will become more of a fire-hose to keep track of.
I've mentioned that there should be a "clear" switch for you to start over and start following people all over again. I also don't think there should be a limit to the number of people you follow.