Pretty simple. Add a bag of ice to the bottom of a large ice chest throw in a hind quarter and a front shoulder, add some more ice throw in the other hind quarter and the front quarter and your trim and cover with ice.
Keep it closed up and drain as needed. The ice will melt fairly quickly at the beginning, but once the meat is cooled to the bone, the ice will last a long time. Replace ice as necessary. I've done two antelope and a deer this year so far with the ice aging method and left them for 12 days. I don't think it hurts to rotate the meat either but sometimes the ice gets really hard and it's hard to access the meat.
As you drain the water, it will be extremely bloody at first, but by the seventh or eighth day it's barely pink. I think it does a good job of removing all of the blood. Everything I've eaten has been very tender and mild.