Down here we just turn them into a pack. Cut the front leg as in the first photo, make a cut in the back leg and thread the front one through as in the second photo, do the same with the other side and put it on your back. No string or anything else required (just a bit of sweat) :-)
Mike,
Do your deer get many ticks on them? If you tried the pack method over here, you'd be alive with ticks before you'd gone a 100 yeards, especially in summer!
Regards,
Peter