Remove the bike seat - plug the cable into the OBDII cable on the bike - plug the cable into the USB port on your computer. Start TuneECU and make sure an appropriate tune is showing in TuneECU - wait a little while as your computer gets to know the bike. This will be evident by the little red, then amber, then green flashing bit on the screen. When it is green you are ready to go.
The first thing you should do is to read the tune out of your bike and save it with its own unique name. That way you can always return to where you were before you started.
This is all assuming that you have first loaded the correct drivers for the cable.