When ordering multiples order each style you want to include in the mix so that they are together in the same shopping cart.  When ordering 3+ designs to mix, the quantity can be a minumum of 10+  for each design (instead of the normal 20 minimum)

You can alter the name for each card, example:

card 1   Mr. and Mrs. Jack Johnson

card 2  Jack & Barbara

card 3  Barbara Johnson