My italian cookbook says to rinse really well, then par-boil (leaves only) for 1 minutes, then
drain, then squeeze out all the liquid, using a tea cloth (use an old one cause it stains)...then use as you would frozen spinach.
(At this point, you may want to drive to the store and just buy a box of frozen spinach. Unless you got yourself a bored Italian widow hanging around who doesn't mind the extra prep steps.)
I start out with armloads of fresh chard big enough to staff Monique's Exotic Fan Dance Club...and end up with a dense lump the size of soft-ball. Intensely dark greens: I'm thinking of the benefit to eyes...my fan dancing days are long gone.
How do you prepare yours?