To get traffic from the search engines you need links to your website, lots of links. This is because the search engines give better rank to pages with inbound links than to pages with little or no links.
Here's an easy way to get links from blog comments. Just type the following search query into Google:
wordpress comments "your keywords"
Where you replace "your keywords" with the specific keywords your are targeting with your website.
When you search like that you will find wordpress blogs related to your niche where you can post relevant comments and include a link back to your site.
Make sure to use different variations of your keywords when you link back!
A good strategy when commenting on blogs is to write something that ads value to the discussion. That way some people reading your comment will become interested in what you do and click through to your website to check you out.
Links from blogs in the same niche as your website is a lot more valuable for SEO than links from random unrelated blogs. The search engines considers the theme of the link when deciding how to rank your site.
Another time I'm going to tell you how to get more dofollow links and what's the difference between dofollow and nofollow.