Automatic Climate Control is just like your house A/C (although, since you live in SF, you may not have A/C ).

When the car is cold, setting the dials to 90 doesn't make it heat up any faster than leaving them at 75 or whereever you'll be most comfortable. Likewise, when the car is hot, setting the dials to 60 doesn't make it cool off any faster. There's a finite amount of heating and cooling that can be created by the system. The fan will speed up or down to increase the rate of cooling or heating. Max fan speed will provide all of the heating/cooling that is available for any given climatic condition in the car. If the inside of the car is 105F, and the temp setting is 75, the car will cool down just as fast as if the temp setting is 60.

Set the dials where you want the temp to be, and (more or less), leave the system alone.

Of course, if you're more comfortable with heat in your face instead of on your feet, you can press the various buttons to move the location of the airflow. In general, the car will provide A/C out of the dash vents, and heat out of the floor vents. Selecting Defrost will send all (or most all) of the airflow to the vents at the base of the windshield.

The red & blue buttons in the center dash vents make the most "sense" (and I use that term loosely) when the car is in heat mode. Pressing the red button will send heated air out of the center vents. Pressing the blue button will send outside (unheated) air out of the center vents. These buttons work in an either/neither mode. Red only, Blue only or neither. When the car is in A/C mode, the red button seems to function the same as the blue button - non-cooled air is delivered from the upper vents. (At least that's what I've been able to determine in the short time I've owned the car - it may be a totally different story when it's 100F here in Houston next summer.).