The best thing to make a blog popular is to create decent, regular unique content. Once you have at least 20-30 good posts, then that is the point of starting to promote it. Do all of the things already suggested, ping, commnet, directory submissions, tell all your friends about it. don't get too wrapped up in the promoting side of things unless you have something worthy of promoting. If you do, visitors will not come back and you will have wasted all that effort in promotion.