After Santa became a little less for ware we would hang the cards on a piece of yarn that we strung along both sides of the hall way.
Grandma Smedley used to scotch tape hers on the doors that faced the front room. When the doors were full she would tape them along the opening between the kitchen and front room.
When I get enough cards I tack a piece of yarn along a wall somewhere and hang them there.
I am fortunate enough to have a few Christmas cards that were sent to my great-grandparents. One of them was from mom, dad & I in 1964.
I still enjoy sending and receiving Christmas cards. And yes, I save every one!