You have to be active on the forum for 4 hours, which isn't easy. Just staying logged in won't cut it, you have to at least refresh occasionally.

As for your question, most pools allow you to create more than one worker, and all of them would mine for you. Just check with your pool of choice if it's possible and how to do it. For example in Slush's there's a "register new worker" link on the account page, and in BitMinter you can do it through the Workers page.