How to memorize discarded cards as an elvoving snapshot

Hi, I am looking for a way to memorize which cards were discarded on the table in order to know if the card I am looking for is still available in the pile.

Most of the card games I play use 2 sets of cards, you have 13 cards in your hands and you need to have either series of the same suit or cards of the same numbers.

To speed things up, I place the cards in my hand in 4 rows, each rows are a different suit and I align vertically the numbers so I can see very quickly in my hand what fit.

I am looking to do something similar in my mind for the discarded cards. I don’t need to know the order, but all the cards are important.

For now I am thinking of placing associated images of each cards in a grid format in my mind and maybe injure them (in fire, 1 arm off, a bullet wound, watever) when only 1 card is discarded and then have them dead when both are gone…

An other idea is to go the other way around, so memorize the card that were discarded, and when you get about about half the pile gone, you switch to those that are still available.

I am looking for something simple that don’t take my full attention since I still want to be able to have a conversation.

Any suggestions?