I usually skin and quarter up the deer and wash the meat thoroughly. I'll then place the meat in a cooler with water, ice and salt. I'll let the cooler ride around in the back of my truck for a day then drain the cooler and fill it back up with ice to carry to my processor. Seems to be the cleanest way I could come up with over the years. Letting it soak in the ice/water/salt mixture helps pull the blood from the meat.