I'm in violent agreement with most of my learned colleagues above.
(1) Master switch off
(2) Fly the aeroplane
(3) Divert if nothing seems to be still burning, land immediately if something does still seem to be
(4) Fuel off ONLY if there seems any risk of fire near the fuel. But if that risk exists, just do it immediately, then fly the forced landing.
(5) IF TIME AND CAPACITY PERMIT, turn off surplus "stuff", then turn the master switch on long enough for whatever combination of RT / gear / flaps seem necessary and appropriate,then off again. If time and capacity don't permit, or there's new smoke as soon as the power comes back, just fly the aeroplane with the master off, and don't worry about the rest of it.
(6) Flapless landings in Cessnas are pretty much non-events - add about 5kn to the approach speed, and expect to use maybe 25% more runway. I've had a C150 electrical failure on a night cross country; the non-radio flapless night approach and landing that resulted, was stressful, but perfectly safe and nothing to write home about.
G