You should start by mashing the mounds down flat. In no time you will see where he is because he'll push the dirt back up. Now you've narrowed down where he is, so depending on your soil type and where you live, you can do whatever works for you. A shotgun blast down the hole will kill it with concusion, a pitchfork (if you have soft moist ground and the mole is shallow) works well by just jabbing the tines along the hole's path (remember, you know where he is because you smashed the mounds down). exhaust from your mower will kill them if you can get a hose around it. I guess you could stand real still and practice your knife throwing skills at the appropriate time as well. Good Luck.