All information was found on: http://www.mmowned.com/forums/world-of-warcraft/exploits/298676-become-colossal-dalaran.html

Song:
Enter Sandman - Metallica

makro:
/script SelectGossipOption(1)
/script UseContainerItem(0,1)

TIPS: You will grow or refresh the hidden growth timer after 10 seconds of drinking the ale. You have about 10 seconds in-between drinks to mount on a mount or walk around as a giant before having to sit down and drink again to keep your size, as this is not permanent and is on some unspecified hidden timer. After you become smashed by the ale you may have a chance to puke. Pressing Esc before the cast finishes will cancel it and save you the chance of losing your giant size.

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