I’m going to start this off by telling you the opposite of everything else you will read: you do NOT need to choose a niche. Take a look around my blog, it’s been four years and I’ve yet to pick. Don’t worry about it.
What do you like?
The most important thing about blogging is you need to write about things you like. It doesn’t matter if it’s not popular (trust me, you aren’t the only person who likes something), it doesn’t matter if you don’t know everything about it (learn). What matters is that you enjoy what you’re talking about. It shows when bloggers are writing about what’s popular, what they think will sell, it’s not what they care about, they’re doing it for the views.
Find Your Folks
This is the only place you’re going to have trouble when you don’t have a niche- but it’s doable. My folks are for the most part other twenty-somethings generally at the same stage in their life as I am. Each person and I have something different in common, all of my folks are from different “tribes” (a term for another post) if you will.
Finding Your Voice
I don’t like to be professional on my personal blog, these are my thoughts and opinions, and I want to write in a very familiar tone. I want people to know they’re reading Mary’s Average Adventures by a line. I don’t want to be authoritative, I don’t want to lecture, I just want to be, so I use my own voice. A lot of my writing is exactly how I talk– run on sentences and scattered ideas. I’m very scatter-brained- the kind way of saying a mess, but that’s me and that’s what I want my blog to show. My voice is not me showing my best self (did I get tipsy and write the other night, yes), it’s me showing me.
That’s not to say that’s the only way of doing things. If I was talking about business that wouldn’t be okay, but I’m not. You have to figure out what voice fits your blog.
This is you.
A blog isn’t meant to encapsulate anyone but you. It’s meant to house your thoughts or information you think the world should have. It’s you. Don’t worry about what’s popular- it’s easy to fall into the trap of what will get views but at the end of the day it needs to be what’s best for you. Don’t burn out over a blog, that’s silly.
Thoughts? New blogs I should be looking at?
Mary Rose Jaskiewicz 
Tell me what you want, what you really really want!