Steve Nicol, that is, the coach of the struggling New England Revolution soccer team. I would concentrate on just a few things, all within the span of control. One field, one ball, two teams, 11 men each side and 90 minutes to play.
Possession: you can score if you have the ball. They can't score if you have the ball.
Passing: small passes, give and go, triangular movement, moving to the open team mate. No long punt from the goalkeeper, a small pass to one of the defenders.
Patience: the small passes, keeping possession will require patience and discipline. When to break or when not to. Don't force what you don't have. Don't make a pass that your teammate can't handle. You wouldn't want that kind of pass either.
Yes, it would be nice to have another player or two. But the game can be played well with those who want to play when they play together keeping possession, being patient and making good passes.