Question regarding seating cards

When a guest is invited with a guest, on the seating card how is it supposed to be written out:

Example
Mr. John Smith and guest

or
Mr. John Smith and Ms. Mary Jones

or do each get their own card

Thanks!

I am planning to give everyone their own seating card, because I am doing the picture frame thing, that way everbody has one. I hope it works though

I am doing the frame thing as well for the seating cards... I will have it read

Joe and Jane Smith

For a single person not with a guest I will put

Mary Smith

For a single person with a guest, if I knew the person they were bringing i will write

John Smith and Mary Jones

If i did not know their names for sure I would write

John Smith and Guest

I agree with SP04,
all of the weddings that I have been to the seat cards read that way.. Because we may not know the guests name so doing seperate ones is going to be tough.. (sp)