When you create a blog you should first choose a "target". what is your blog' s purpose?
1. If you wanna have a blog just for getting visibility, you should write almost 1 article per day and post it in your blog.
Write article that follow the topic of your site but "dropping" most searched keyword in your content
2. If you wanna have just backlink, use your energy and your content posting your article in guests blog.
I see a lot of blogs that set theirs link "do-follow". If you don't want to see your page rank improve and don't let your blog
being filled of stupid/no sense fake (SEO) comments, i think that you should keep no-follow setting.