You'll want to sort your cards by color. It's great to involved the children in cleaning up so they expect that after each game. Ask one child to get all the orange cards.
Ask another to get all the yellow cards. If someone is making a commotion to get a turn, politely ignore the “noise” and call on students who are quiet and polite. If the children are well-behaved it's fine for several students to be cleaning up their rows at the same time.
Ask the students to place the cards in your hand with “straight corners”. This will them so later they will be able to do this without your hand being there. This will free you to prepare for the next game.
They will enjoy the clean-up a lot, and your cards are all ready for the next time you bring them out.