Well there is an easy way ?? get the ultimate TAG warrior plugin, what this does is adds and addition text box where you add your tags to each post.
Let’s say you have a post about racing cars, well you put tags like cars, racing, nascars, fast, burnout etc in the tag fields.
Also if you want to get listed on yahoo, google etc a xml sitemap would be useful, this type of sitemap tells the search engines what files, post, pages got updated and the search engines will read that post and add it to their index, again a plugin will help you with that, either SEO or google sitemap plugin.
best of luck.
