I am a newbie SRT6 owner and it only has 36k on it.

I am getting error code P0303 Cylinder 3 Misfire. The two times that the car has ran ruff and I received this error was after the car had been sitting for only a couple of hours so it wasn't when it was completely cold. It started fine, then after I was moving it starts to run ruff, I pulled over and turned the car off both times restarted it and it ran fine. The check engine light does come on and stay on.

1. How do I identify cylinder3?
2. Can anyone recommend an ordered course of action to help me troubleshoot and fix this?

Thanks
Steve