A big question when creating a blog is “What am I going to talk about?”. You have no clue what subject you’re going to choose.
The best tip I can give you for this is talk about something you love! You’re creating a whole website for blogging why not make it something you love?
If you love cooking why not make it a site about cooking? If you’re a mother and love your children why not write about raising them? No matter what you choose it’s going to be hopefully something you love.
Here’s the best part though! It’s alright if you decide not to stick with your subject. That’s probably the best part of all this. You can either make a new site and write about something else OR you can make categories.
If you’ve got different things you want to talk about why not make a category on your site? Then people who come for different things will know where the posts they want to read are! This also in return gives you room for more ideas. More ideas turn into more content.