A couple of years ago I was shown a method that works very well with an Excalibur.
Put your foot in the stirrup. Take your rope cocker, put the hook right against the handle on one side and hook it to the string. Put the long side of the string in the groove to the other hook and attach that hook to the string on the other side of the bow. At this point you have both hooks on the string, the majority of the rope hanging out on one side, and a short length of rope in the groove at the back of the receiver. Tighten your pressure on the long side handle to put some pressure on the string. Release the safety, and pull the trigger keeping firm hold of the long side handle. Gradually let the pressure off with the long side handle. I leave my bow like this (hooked up to the cocker) over night, but its a simple matter to unhook the string at this time.