If you have run a blog yourself, you have probably been conscious of the tendency of occasional “readers” to leave comments with little relevance to the posts. Occasional comments like “I like this! Great post!”, or “You should talk about this subject more often”, when they appear without any context, are comments to look out for.
The fact is that where you see these comments, it will usually be because the poster is trying to drive up traffic for their site. You will usually notice that their name appears as a link on the comment, and when you click it you are taken to their site. This is a simple method of promotion – and it bugs many bloggers to the point where they will delete all such comments.
This does not mean that you cannot use blog comments to promote your own site. There is some advantage to doing this if you do it correctly. First of all, you need to comment in a suitable way. Just saying “Great post!” makes you look at best like a sycophant, and at worst like someone who hasn’t read the post and simply wanted to see their name on screen.
Make sure you are commenting on a blog with relevance to your chosen topic. This will mean that people who click through may be interested in what you have to say. Actually read the post before commenting, too. When you have done this, you can ensure that the comment you post is relevant to the blog post and means that people who read it will be more likely to click the link and come through to your site.