I got the Dick Smith device and am ready to tackle jobs. What
techniques/hardware are being used to make sure that capacitors are
properly discharged? I will be working mostly on older stereo
equipment. My understanding is that the non-power supply caps will
discharge after the equipment is turned off. For a typical cap to be
found in this application, what would be a good way to survey the board
and discharge the caps? What size and type resistor? I have a bunch
of audio grade sandcast types from partsexpress, would these be good
enough? Should I even bother or are these caps inoffensive?

The power supply caps, which I am guessing are identified by size and
proximity to the power source are a different animal. What should be
done about these?