Having another player take my turns [Outdated]

I'm sure this has been posted before, I just couldn't find it. My question is: What is the proper way to let another player take turns for you while you're out of town/otherwise unable to play? Is it enough to just tell the other players, or do I need to tell the mods? In my case, the only game I'm in has not started yet, so I just sent a PM to all the current players telling them my friend would be playing for me.