Use your primary and secondary keywords in the anchor text of links when linking to other blog posts or to other pages of your blog.
Keyword in links have more importance than simple text. This is major to the search engines, ANCHOR TEXT IS VITAL!
For example if you want to rank using the keyword diving then make sure all the links to the site use the word diving like this: diving
Don't just put in the code http://www.diving.blogspot.com, use the link button in the posting WYSIWYG editor and highlight the keyword, like this: diving