Here is an unordered list of advices to improve your blog quality as well as your blog ranking on search engines:
- Write good content (trivial but have to be noted)
- Answer to comments from readers as often as you can
- Add your blog address in your e-mail signature
- Participate on forums that are related to your blog topic
- Add your blog to web directories
- Put a link to your RSS feed on the main page of your blog
- Tag your own posts (and others) on social bookmarking services such as Delicious, StumbleUpon, Digg, Reddit, Sphinn, etc.
- Ping your blog - and blogs linking to your blog - on Technorati
- Use keywords in the title, headings and top of your posts
- Interlink your own posts in your blog to allow the reader to find more of your content
- Ask questions and invite comments at the end of your posts
- Keep up-to-date with search engine optimization (SEO) using forums and blogs
Hope this helps!
Feel free to answer and add your own tips...

Tags: SEO, blog, engine, optimization, ranking, search