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To give you a brief run down though, the first thing you should think about doing is creating a Blogger account on Google. It's free and Blogger allows affiliate links. As mentioned before, you need to write up some articles related to your clickbank product and post them on your Blogger with your affiliate link.
Do your best to write keyword targeted articles. Obviously, the keywords need to be related to the product you're trying to promote. Check out Google Adwords Keyword Tool to help you find keywords to write your articles around. You're looking for keywords that don't have a lot of competition. Any keyword that has between 25,000 and 50,000 searches a month would be good to write on.
When you're writing your articles, try to only use a 1% to 2% keyword density. That means using your keywords once every 100 words. I usually recommend using your keyword phrase once in the title of your article and about 3 times in the body.
Using targeted keywords is important for SEO, which will give your articles Google visibility.
Submit your articles to directories such as Ezinearticles and GoArticles, and post a link back to your Blogger account in the author bio box. Ezinearticles generates some pretty generous traffic.
Create an account on Squidoo and make a lens with your product related articles, linking back to your Blogger account. You can also rewrite your articles and post them on Hubpages.
Another method you could use is to sign up on a few forums related to your product. Put a link back to your Blogger account in the signature line and try to post helpful content on the forums daily.
Those are just a few ways to get traffic for free, but there are quick a few more. If you're interested in learning how to make money online, you should check out my website My Making Money Internet When you sign up I'll send you a free ebook that will explain a lot of this step by step. You'll also gain access to my blog, which includes a wealth of information designed to teach people how to make money online.