How to Choose Cards & How to Discard Them. When dealt a new hand of rummy slots, it's crucial to carefully consider which cards to keep and which to dgames appiscard. When it comes to forming strong rummy hands, players should try to hold onto the cards that have the best chance of doing so and discard the less likely cards. In order to form a winning rummy hand, players must consider the potential value of each card in relation to the overall objective.