How To Upgrade Wordpress

I've been keeping the old version of Wordpress to my blog and been very guilty but also too lazy to do anything about it. The turning point was when I'm going to change my template and realize that I can't installed the new templates because it won't sync with my older pal. After I read the news about Wordpress under attack, I become more and more enlightened to upgrade and share it with you. I didn't know if there's a more easy way to do this, but here's how I upgrade my Wordpress.

Cara...