it's a behavior that i had kind of unlearned over the years since leaving Tumblr and moving almost entirely to Twitter, and for good reason! A lot of times, these things feel like Entering Into A Contract with the followee, and sometimes this contract is even codified into follow-for-follow type behaviors to juice numbers.
my own strategy kind of ends up at "oh, i like this post a lot! i'll click into this person's blog" and then i'll toss a follow if their first half dozen posts or so pique my interest. (hell, that bar is sometimes "if their posts aren't things i actively dislike!") It honestly hasn't failed me yet; obviously YMMV if you have more stringent or specific triggers/preferences. I don't think i've unfollowed anyone that i've followed this way, and i'm the type of person who fully subscribes to a "hit da bricks" philosophy when it comes to stuff i don't like or don't care for. More often than not, that rando i just followed writes some sort of essay length exploration of A Thing I Dont Care For and i come out the other side Caring For that thing. It's neat!
just follow people! 
it's easy, free, and totally reversible.
give it a shot :D
I have made a lot of friends across many platforms by just being "Oh you look cool, I'm gonna follow you!"
And some of them have become great long-term friends. Some of them are just casual acquaintances, some of them we ended up not really getting along and quickly went our separate ways.
You won't know unless you try.