Determine Which Cards Are Valuable. On the other hand, retaining cards that opponents frequently pick up can indicate that they may be valuable in subsequent turns. Playewhat is pci slotsrs can spot valuable cards and modify their strategy by keeping an eye on the cards their opponents pick up. Players can improve their chances of winning and maintain an advantage over their rivals by using this strategy. Adjusting to the game. The ability to adjust to the game as it develops is ultimately the secret to success in rummy.