How do you set the time on a casio g shock watch????????

I had the same problem following recent daylight savings time (DST) change. The watch has three DST mode settings (ON, OFF, and AUTO). You get to the setting mode by pressing and holding the "adjust' button until the city time zone indicator starts to flash. Then press the "mode" button. This should give you the DST setting. Now press the "receive" button to cycle through the ON, OFF, and AUTO modes for DST. I set it for AUTO. I then existed the setting mode by pressing "adjust" again.

Now you can initiate a manual update of the time by pressing and holding the receive button. Put your watch by a window and make sure the signal strength indication is showing level 4 (full picture of satellite dish on my version). Give it a few minutes to down load new time.

After doing this the watch corrected itself and now shows correct time. Other wise I assume you could set the DST function to ON or OFF as well depending on whether you need to add or subtract the hour from the time.

The recessed button where it says RECEIVE (4 oclock position).  Push it and you will see the last "GET TIME", i.e., the last time the watch synched with Ft Collins atomic clock via satellite.  It should have todays date, usually ~ 3 AM or something.
If not, then your watch is having trouble synching with the satellite.  I am having this problem now.  Today is Nov 5.  My last GET TIME is Oct 30.  Which means I have non adjusted for Daylight Savings time TIME on my watch.  I am an hour off.  Not sure why mine won't synch up.