How to use multiple Facebook accounts in same browser

>It's  easy  just  login  to your 1st Facebook  profile with  your browser
>open  new window  and go  to  proxysite.com
>Now type  Facebook.com in url box of the proxysite website
>you want to use more accounts just open new window  and do the above steps
>Now you can Use multiple accounts  in the same  browser!