Columns Alpha Trinity theme

I’m very new to WordPress, and it would be greatly appreciated if someone could point me in the right direction of how to create three columns on the Alpha Trinity theme…

Best advice I’ve found, but am hopeless when it comes to CSS:
http://vip.wordpress.com/documentation/how-to-create-columns-in-posts/

There’s not much here yet, http://www.kylieking.net

Kylie