How to login with different users to Report Manager

Hi,

I'm logged on my computer and can access Report Manager with that domain user without prompting for authentication. I also have a test user, with which I'd like to test the security settings. However, I don't know how to log out as there's no a button for that purpose. How do I log in with the other user?

I'm using SSRS 2008 and IE10.

Thanks.

P.