Do it! It could very well end up being one of the best decisions you’ve ever made.
Once you’ve made it, try to find some other writing blogs to follow, just so you can form a sort of writing network to gain inspiration and followers from. I have a list of writing blogs that I follow here that you might want to check out: http://writingsforwinter.tumblr.com/writingblogs
You can also do some collab pieces with other writers, which will give you experience writing with someone who has a different style than you.
Or join some tumblr writing networks, i.e. www.thewriternetwork.tumblr.com.
Posting at least one piece daily also helps ensure that your blog stays current and updated.
Good luck! :)