I am color blind as well. My difficulty is on wet leaves and the like. Once the leaves have dried I can follow it.. On my moose hunt it wasn't bad as I had my sister start me on the blood trail and then I could follow it right along. So I know it can be difficult to follow. When I loose the blood trail I mark the last place I saw blood and start circling making each circle bigger while looking for where it may have run. I also look for a deer walking with his toes spread.. They tend to do that to help maintain balance when wounded..I hope this helps you.. I have recovered quite a few deer this way..