There are no procedures except land as soon as possible.
If the geomagnetic disturbance from the flare is severe enough, radio doesn't work, radar doesn't work, and GPS signals are lost. Radio based navigational aids will also fail or be unreliable.
So strict VFR flying conditions with no external contact between aircraft and the ground or other aircraft and no navigational information except eyeballs and paper charts. Even that may not work if compasses are inaccurate, as they often are that far north in geomagnetic storm conditions.
Still want to fly?
Sometimes we just have to recognise that nature is bigger than our technological solutions.