I have a new home with a gas fireplace. I am told you should shut off the pilot in the summer as it does produce heat. How do I go about trying it off?

There was no manual with a new house? Most units have a grill under the unit. Lift the grill slightly and it should flip forward from the top. Should be a small knob that says OFF-PILOT- etc. Rotate knob to OFF, you may have to push it in slightly. To restart, rotate knob to pilot, push in knob and hold, depress ignitor button until pilot lights, hold Pilot button in for 15 secs and release.