Blog for the fun of it and show character. It is immaterial how many write about a particular subject, it is how you write the matters.
Engage readers with well-researched and creative blog posts. At the end of it ask questions or feedback from them.
Image speak - A lot of bloggers tend to ignore this, but the images on your blog speak a lot for what you write. Use good quality images and make sure they express your written stuff in utmost simplicity yet precision.