SEO is best one to increase traffic for any kind of websites. SEO service. You can get the SEO service from http://www.xnynz.com/search-engine/seo-services.aspx?ci=1808&prog_id=456858
here they provide Search engine visibility service which bring traffic to your website. Here they provide you One-click submission and Google keyword generator of your site in many search engines like Google, Yahoo!, Bing, and AOL etc...
You can add meta tags in different ways, depending on the tool you use to create and update your site.
Admin CP -> vBulletin Options -> General Settings -> Meta Keywords