Tongue hanging out, excessive slobbering, being a bit listless while walking similar to someone that is drinking alcohol, looking thinner than they should be. Other than that, you can't tell if it has CWD, and just have to hope it doesn't.

That said, you can chop off the head, and send it in to local facilities that will test it, this is actually encouraged, so the authorities can better map infected populations. In the meantime, you just let the meat sit in your freezer until they report back.