Keeping a careful eye on the cards your opponents are discarding can provide you with important information about their hand & assist you in choosing which cards to keep & which 21 slotsto discard. It's also critical to maintain track of the cards that have been played, as this will enable you to distinguish between the cards that are probably still in the deck & those that are still in play. Another key tactic is to keep an eye on the sets and runs you are attempting to form and modify your plan in response to the cards you are dealt.