if you always fall asleep when on the ground get into the habit of waking up by not moving anything and opening only one eye at a time, please follow instructions from someone who has snored in many deer..
upon waking sit motionless (no twitching, or farting or trying to get feeling back into the leg that fell asleep) peel right eye lid open very slowly while eye ball is rolling back and fourth scanning that whole right side area, after right eye is fully open and still blurry from the nap,, begin slowly opening left eye while rolling that eye around doing the same as the right eye,,,,,,, once both eyes are open and you determined best you could through the blurry vision that there is no DEER standing there starring at you! you can continue rolling both eyes around at the same time while thinking about how tired you are,,,, move the legs and arms that fell asleep and are now needles and pins torture to a better position then drift back off to sleep and do it all over again when something else wakes you, or if its getting close to lunch time wrap it up.