I wouldn't waste my time on blog comment backlinks because when you create a backlink using blog comments, it's usually no-follow.
A lot of the times, people use this technique in a very spammy way.
There's even specialized software that blasts your link all over the Internet through blog comments.
You best believe Google is wise to this.
I wouldn't even mess around with it.
Instead, I'd focus on actually newsworthy press releases so authoritative people and bloggers in your niche would naturally and voluntarily link to you if you have something interesting to say in your press release.
Another approach would be to get active on social media spaces where people who observe your niche participate in discussions.
Once they see that you are a legit authority in your niche, they may make you part of the conversations they engage in.
They might invite you to do guest posts.
There are all sorts of possibilities, and it's all about putting yourself out there as an expert.
Remember, nobody is going to care about what you know until they are sure and they know that you care.
The way to do this is to demonstrate your expertise by helping people with information and not linking to your blog every other post.
I would suggest that you just help people for about a month, and then once they see that you're legit, then you could start sharing your links.