Scan the hook QR code with Xaman and send 10 XAH to it on the Xahau Mainnet.
Step 2:
Wait, you will receive 20 XAH if you win, you won't receive anything if you loss. (Waiting time can go from 1 second (if you are the 2nd player) to whatever amount of time until a 2nd player enters the game (if your are the 1st player)).
Step 3:
You can check results in the hook account by cheking the Mainnet explorer to see the corresponding Ledger_Index of each transaction, if both are odd or even, 1st player wins, if both aren't odd or even, 2nd player wins: https://xahau.xrplwin.com/account/rGgg27dQggoGGia34HsvgJfaEUkK6heBvq