The objective of Oklahoma Gin is to be the first player to form valid sets and runs of cards with the lowest possible total points.

At the beginning of each hand, 10 cards are dealt to each player and 1 card is placed face up in the center of the table to become the upcard of the discard pile. The remaining deck is placed face down next to the discard pile and becomes the stockpile.

If you are the dealer, your opponent has the option to take the upcard from the discard pile and play first. If your opponent passes, you have the option to take the upcard and play first. If neither player takes the upcard, the player opposite the dealer draws a card from the stock pile and plays first.

Players take turns. On each turn, a player can either draw a card from the draw pile or the discard pile and then discard one card onto the discard pile. The player's goal is to form melds in their hand.

Using the same card in more than one meld is not allowed. Any card in your hand that isn't in a meld is known as deadwood and has a point value. Aces are 1 point, face cards are 10 points, and all others are valued by numerical rank.

During Gin Rummy, you may choose to end the hand when the sum of your deadwood is 10 points or less. In Oklahoma Gin, instead of 10 deadwood points, the rank of the initial upcard determines the deadwood limit for the hand, with an ace requiring 0 deadwood points before knocking. If you can't knock yet (or choose not to), your turn ends when you discard. You must knock if you have 0 deadwood points. If you can knock with 0 deadwood points, you are said to be going gin.

If only 2 cards remain in the stock pile, the hand ends in a draw and the same player deals again.

Knocking Players can knock as long as all the cards can be combined into valid sets and runs. To knock, a player discards a card face-down and declares that they are knocking. The other player then has a final turn to lay down their sets and reduce the value of their unmatched cards.

If you are not going gin, your opponent is entitled to lay off any deadwood that fits into your melds.

If the knocking player's unmatched cards have a lower total point value than the other player's unmatched cards, the knocking player wins the hand and scores points based on the difference. For example, if you knocked with a run of 8 through Queen in spades, and your opponent has a 7 of spades, your opponent may lay off the card onto your meld and reduce his deadwood count by 7.