Building a successful blog takes a ton of hard work. It's not a case of posting up a few articles and hoping for the best.
Firstly you'll need a regular publishing schedule and to dedicate time to producing your blog posts. The most important thing to know about blogging is that it takes a lot of time to create something worthwhile reading, both in the execution of your blogging strategy and building up a body of work that is a valuable resource for your readers. A lot of people give up because they don't see immediate results.
You won't, but don't let that put you off. Blogging is the most cost efficient route to market in the long term. Short term you'll need to use other promotion strategies like PPC to make sales and keep a roof over your head, but over the long run, blogging will pay for itself many times over.
When the traffic starts flowing from your blog posts you'll be thankful you started making this strategy work for you.