wrestling

when i go over to my friends house we occasionally get into wrestling/fighting matches and i have trouble holding my own because i don't want to seriously hurt any of them
any techniques i could use?

If you are interested in learning to apply submission techniques, locks,holds and chokes etc perhaps you might like to look around your area for a Wrestling ,Ju-Jitsu or Shoot Fighting class or anything similar to the above. It's a bit difficult to describe safe techniques by the written word. Demonstration by a qualified instructor should be your next step. Good luck in any case
Regards

Many Aikido terchniques are very simple. One should remember that when employing a lock/hold, is that it is the opponent struggling against it that causes them pain, not the one employing it.
when you have your friend in a hold, calmly remind them of this.