At the "Press Start" screen, press X, X, White, White, Y, Y, White, X, Y, Y, X, White.
At the "Press Start" screen, press Y, Y, White, X, X, White, Y, Y, Y, X, X, X.
At the "Press Start" screen, press Y, X, White, Y, X, White, X, X, Y, White, X, Y.