1. Download World of Warcraft 3.3.5a. --- Windows: LINK1 | LINK2 | LINK3 ||| MAC: LINK1
2. After it's finished downloading, go to your
World of Warcraft/Data/EnUS or World of Warcraft/Data/EnGB folder, and search for a file called realmlist.wtf
3. Open it by right-clicking on it, and replace everything that's written in it with
set realmlist pbwpro.com
4. Create an account at: http://pbwpro.com/register
5. Log in with the credentials you just chose at point 4.