Blogging is actually not the hardest thing to do. But without traffic, you are just writing to yourself. However, here are a few easy things that will make sure you get visitors to your blog:
First, blog often - at least twice a week. This will increase the chances that the blog will be indexed by the search engines. Continually adding content will increase the likelihood that people will return often to read the blog.
Another method of increasing blog traffic on your own blog is to visit other people's blogs and post comments. Simply posting comments like 'I agree,' or 'I will try that,' is valueless and spammy. To encourage the owner of the blog to accept the post, always make useful comments or suggestions. The owner is much more likely to accept such a post, and your time will be well spent.
Don't JUST comment on posts. It's good practice to link to a good post on someone's blog by posting a link to their blog on your blog (whew, say that three times fast!). When you do this, they get a Trackback notice that you have linked in. If you do this a few times, adding value each time, eventually the other blogger will link back to your site. Soon, you will start to increase blog traffic.
Try to link to blogs that are complementary to your affiliate marketing niche. You will have better luck this way than trying to link to blogs that are in direct competition to yours. For example, if you have a blog in the dating niche, it might not work out to well to contact others in the same niche; you might be better off visiting a travel niche and finding some posts on "Romantic Getaways" to link to.
Make sure there is a way for visitors to subscribe to your blog: People don't always bookmark blogs anymore, and if they do, they may still never get back to them. So make it as easy as possible for them to get your information. Have a Newsletter Subscription area, or a Feedburner subscription option.
And, always have your RSS button displaying on your site. Many people will put your RSS link into their Yahoo! Membership area and read from there. You want to make sure it's easy for them to find this important link. As you increase blog traffic, you also want to increase your subscriber base for future sales.
Consider carefully exactly what you hope to accomplish with your blog. Although it is designed to make money, simply putting up many advertising banners and affiliate links will cause people to tire quickly of reading the blog. These advertisements and links are useful, but only when used in a way that doesn't overpower the reader or the blog.
I'm not saying that banners and affiliate links are a bad thing - just use them efficiently and not in an over-powering way.
Your goal is not only to increase blog traffic, but also to become known as an expert in your field, so that visitors will want to return to your site to learn from you.