Good morning Mark--
From when I last did this to my Flair a year or so ago, it wasn't particularly difficult, it just required some time / patience and ideally having an oven thermometer meant for the purpose, meaning one with a remote probe inside the oven with a display / readout outside the oven, and you close the door down over the wire.
If (say) 350 degrees is the temperature at which you bake most things, use that as your target temperature. If you usually bake things on a rack in the middle of the oven, put the temperature probe in the very middle of the oven. Set the oven to 350 with your thermometer in place, and let it heat up and cycle on and off a handful of times to stabilize, and observe the range of temperatures. They key thing to keep in mind is that the oven temperature will fluctuate over a range of temperatures, the "cut in" and "cut out" temps. If 350 is your target, the goal is to have the thermostat cut out (stop heating) at 365-370, and then cut back in (resuming heating) at 335-330. Yours may have a wider or narrower range of temperatures, but that's about what I recall from mine.
In order to make the adjustment, with the oven temp knob set to 350 (or whatever is your target temperature), pull off the oven temperature knob. Within the protruding shaft of the oven temp switch is a small screw (I believe it was slotted, requiring a small flat-bladed screwdriver) that you turn to adjust. As you tighten or loosen that small screw (only a little at a time!), observe how the cut-in and cut-out temps shift up or down over a few cycles to see how far you are from having your target temperature in the midpoint of the range between cut-in and cut-out. The goal is for your average temperature to be your target temperature.
If it is not possible to adjust the temperature to center on your target temperature, it could be that the temperature probe in the oven is dirty or damaged-- you'd have to do a visual inspection to assess whether either is the case. A gentle cleaning of the probe may help if it is dirty, but if damaged you'd then need to replace the entire switch and connected temp probe.
Best of luck, and best regards,
Christopher Burns
Christopher Burns P.O. Box 92207 Rochester, New York 14692-0207
(585) 234-3524