This seems quite easy (which means I'm sure I'll get it WRONG!). Each golfer is a number, 1 through 12. Assign these 12 golfers the following group numbers:
1. A, a, a, a
2. a, b, c, d
3. a, c, d, b
4. a, d, b, c
5. b, b, b, b
6. b, a, c, d
7. b, d, a, c
8. b, c, d, a
9. c, c, c, c
10.c, a, b, d
11.c, b, d, a
12.c, d, a, c
What did I win? Everyone plays with different person, each day.
Sad to say, but you did. Golfers 1, 5, and 9 never play each other, for example.
CRAP! An error. I'm reviewing it, I think I am close.