All drummers have different heights, length of arms and feet! So, as already stated, put them where you feel comfortable to hit them at. Not too close or far away, and as Dairyairman said (didn't know you were on here, hello!) not too tall and flat! Your supposed to hit them with a 'glancing bow,' NOT at a 90 degree angle in relation to the stick (slight exaggeration!) so it cuts through the stick like a knife through butter!