If your blog is hosted here on WordPress.COM one of the very first things you can do to help promote your blog is link your username to your blog. That way when you post here or leave a comment on someone else’s blog, the link back to your blog is immediately available.
The instructions are in the post at the top of the forum “8 Things to Know”.
Then, do a search for “blog promotion”. This topic has been covered quite a number of times before.