Observing the Moves of Opponents. Keeping a careful eye on the cards your opponents are discarding and picking up is a crucial component of any winning strategy. Making educated decisrummy cash games apkions about which cards to pick up and which to discard can be aided by learning important information about the cards that are still in play. Cards Should Be Discarded Carefully. You also want to be careful about which cards you are discarding because you don't want to unintentionally aid your opponents in forming sets & runs. Forming Quickly Sets Up and Operates.