Big Sur is one of my favorite photography destinations and Pfeiffer Beach is at the top of my list of specific locations. Located two miles off Highway 1 down the winding one lane Sycamore Canyon Road, Pfeiffer Beach is not to be missed. Although this may not be the ideal beach for a picnic due to the near constant wind, the scenic beauty can't be beat. This is a day use only area with a $5 entry fee. I did find it annoying that although this is a National Forest beach it's managed by a private company that collects the fees and therefore the Interagency Federal Lands Pass is not honored, however it's well worth the $5 investment.
Sunset is the prime time to visit. Photographically, November thru February are the best months to visit. At this time of year the sun sets further south and lines up with the arch. The other advantage to visiting at this time of year is that clear skies and sunsets are more likely, during warmer months inland heat draws the fog into the coast. The first time I visited was in September and although it was still incredibly dramatic it was so foggy you couldn't even tell where the sun was in the sky, it just eventually got dark, without any golden light.
If the conditions look promising and you want to try to photograph the arch, with the spray of waves crashing through it lit-up by the setting sun, be sure to arrive a little early. The effect is most distinct from about an hour before sunset to about a half hour before sunset. During that last half hour of the day, when most people seem to arrive, the sun is all ready too low on the horizon to really give the mystical effect seen a little bit earlier.