The Mental Game of Polo by Bill Cole provide mental strategies that help people win games. Polo is as much mental game as it is a physical game. He provides a solid article of the softer things associated with polo. You may want to read it for yourself.
The 4 mental strategies are.....
Think Correctly: Think positivity and don't psyche yourself out.
Stay Calm and Energize: Learn to meditate and stay calm.
Managed Down and Up Times: Know how to manage your down times and up times to maintain focus when it is needed.
Believe You Belong: Know that you should be there playing the game and in the game.