The background should be 2 stops brigher than the subject.

Easy. First of all you should have little to no
dark tones in your image. Blondes work better than
dark haired people. White clothes, white walls,
white furniture, and a soft lighting that creates
as little hard shadows as possible.

The often heard advice to "blow out" a background
or to overexpose is pure rubbish. A high key shot has
the majority of tonal values in the right third
of the histogram, flat, soft lighting and little
to no visible shadows.

Expose correct (meaning you don't let the camera
meter decide for you), zone system helps.

Develop like normal, and print like normal.
Unless you do something wrong, the proper
lighting and camera setting should enable you
to print high key shots with the same settings
as low key shots. Do your homework before and
set camera and lights right, then you don't have
to fumble around in the lab.

You want a smooth wash of light from one end to the other.  fall off in one
corner or side will cause a few irritiations when printing, especially if
you ever shoot color.

I used to bounce a couple heads into the upper side walls of the studio,
sorta like making the walls and ceiling a huge umbrella.  Ideally you would
have four lights crossing the background, just like lighting art work with
heads all around.

I had plenty of room to move the subject away from the wall.

Light your subject.  It seems folks think that they don't need much light
cause of all the spill bouncing off the back, probably the same folks who
expect the spill from their lights to light up a dark background on low key
images.