1) Submit posts to "article directories". They are websites which post your articles and link to your blog, sending you visitors. A good one is http://www.ezinearticles.com/
2) Contact other bloggers that share your interest / topic area and ask about guest writing on each others blogs.
3) Create some sort of contest for your blog. Have a Blog Carnival (more later on about that). They draw visitors to your blog. Some questions to ask about the contest though, from blogclout.com
- How easy is it to enter the contest
- How fun is it to participate in the contest
- What rewards and incentives can be won
- How to generate the first few participants for the contest
- How easy is it to spread the word about the contest