Disclaimer: Like my other guides, this is based on my experience on whats worked for me. I've only just got my first 40 followers!!
Nobody disagrees on the role of comments in building a following. Commenting is an easy way to engage with your audience and to gain followers. So lets look at some examples.
"Upvoted, followed and resteemed, plz foll.."
Wait! Before you submit that comment lets think about it. Is your goal to increase your number of followers on the hope they will engage (upvote/comment/resteem)? Or do you want to create a following who really interacts with you and your content because they want to?
But surely you can create an engaged following from them?
Anyone following are going to follow out of obligation. As far as reasons for doing things is concerned, obligation is barely above pity. Obligation is the mandatory greeting at the supermarket checkout. Its the minimum required politeness. Do you read a blog of a person you followed because of obligation? Are you going to use one of your 10 upvotes on that persons next article? Probably not
So how do I build an engaged following through comments?
I generally follow these three steps
1. Find stuff that grabs your attention.
Where do you find stuff?
I prefer the new tab (the trenches) for content. Its got a lot of interesting but usually unloved stuff that I love bringing to the attention of others. Its also full of shit but for me finding the gem in the shit is worth it.
Maybe you don't have the patience/time, Narrow it down to a topic and/or go through hot/trending/promoted.
What am I looking for
Find something that grabs your attention. Quickly before you change your mind, read it. Did you enjoy reading it? Check the comments. Do you feel like you can contribute something?
2. Make your comment add something
I have a rule for commenting (and life)
"If your comment wont add something, don't comment"
Example story:
I was scrolling along the new feed, and I stopped at this:
The thing that made me stop was the red lips & how vividly red they are! It stood out, I had to know more. So I read her intro, had all the usual "I like travel and finding myself" but I noticed down in the comments section no-one had mentioned her crazily red lips. So I did.
I didn't feel like I could add any more then she did in her reply, so I didn't add anything. I like to believe I made a difference in her day by noticing & I gained a follower, which brings me to my next point
3 Notice the shit people do
You know when you get a comment that brightens your day? Especially if its totally out of the blue, unprompted and with no expectations of reciprocity. It may of only taken a couple of seconds to think up and say but that one simple action that makes us feel appreciated can mean the world to the person.
So how do we make it count?
Make it specific to the articles intent
Doing this means that you cared enough to read the article. A simple comment can be as effective as a complex and well thought out one, its more about intent.
Be authentic
The modern world has trained peoples bullshit detectors so well most people can spot bullshit at a glance. It isn't worth it if your goal is long term engagement, being inauthentic can cost you in the long run.
Avoid critiquing
Even a well constructed, non-bias critique from someone you trust is a hard pill to swallow. From a stranger, at best its a waste of time, at worst you aggravate someone for no gain. Its up to the individual to see where he lacks and improve himself, your time is better spent doing basically anything else.
What will all this stuff achieve?
A good comment is like a taste & people will naturally follow you to see what other tasty things you have to offer or even just to reciprocate the warm fuzzies. Share with them more cool gems you sifted through shit for and you'll gain a rep for offering up the good stuff and the gems will get more love from your followers. This is getting too mushy for me, so I think i'll end it here.
To Recap (or TL;DR)
Don't spam, find interesting content, read the content and write authentic comments that adds something. The person feels warm in their feelings and then follows you. You resteem the interesting content and your followers get more interesting content and you get warm fuzzies for unearthing and sharing stuff you think is cool!