You use the mode button to select which function you want to view (ie; trip distance, hourmeter, trip hours etc etc.). You press the mode and set button together to clear any meter (ie; to reset your trip meter, you would use the mode button to select that function and then press mode and set together to clear the meter). The set button is used to set the clock and the fuel flow meter if you have one installed. Hope that helps. You can go to the Yamaha website and download a manual in Adobe PDF format for free.