You have a variety of options to meet the minimum requirements to get a refund on your ticket:
Option 1 (Street Team): Six shifts from Oct to Dec.
Option 2 (Pre Festival): Two full days on site any time up to the 24th Dec.
Option 3 (Festival): Three shifts between 26th Dec and 1st Jan - including one compulsory night shift (starting after 4pm) OR four day shifts.
Option 4 (Night Festival): Two night shifts (starting after 4pm) between 26th Dec and 1st Jan.
Option 5 (Packdown Crew): Complete 7 shifts from 2nd to 8th of January 2013 (special conditions and incentives apply).
Shifts are 5-6 hours each including sign in and out and any pre-shift briefings, although maybe slightly longer or shorter, depending on the role.