My father was an all-state centerfielder when he was in high school, he also drank enough to kill a silverback gorilla. He'd take me out to the fields at a young age and teach me the perfect stance, how to field a ball, the mechanics of throwing from the infield and outfield. It was actually pretty easy to learn.
He'd set up near the pitchers mound with a cooler of Old Milwaukee and a folding chair. As he drank and got more and more drunk I would work on basic things like baserunning and sliding. Anytime I did something incorrectly he would throw the empty bottles at my head. By the time I was in high school I was batting over .500 every season, I always hit the cutoff from the OF and I never made baserunning mistakes.
My suggestion to you is take some time with this guy, teach him some things and in the end enjoy watching him grow into a better player. Also, when throwing an empty beer bottle, go sidearm...over the top will tend to drift right a bit.