Gin Rummy adheres to the documented rules of Hoyle's Rules Of Games, but provides rule variations should you be familiar with other methods of playing. Both the Oklahoma Gin game and the Hollywood scoring method (favored by movie stars in World War II) are fully supported.

Ten cards are dealt to you and ten to your opponent. The remaining cards form the stock and are placed face down by the table. The top card is turned face up on the table. This card forms the beginning of the discard pile.

The game progresses with the player or the opponent starting their turn. If this is a new game, the loser of the previous game starts. If this is a new round of an unfinished game, then the loser of the previous round starts. The player who is starting has the option of taking the card from the discard pile. If this option is declined, the other player can elect to take it instead. If this offer is also declined, the first player takes a card from the stock.

Whether you started your turn by taking a new card from the stock or by taking the card from the discard pile, you continue your turn by determining whether you can, and wish to, "knock", which will signal the end of the current round. In order to knock, you must be able to meld cards from your hand to the table such that you will have ten or less points in your hand after discarding. If you meld all ten cards, you have scored "Gin". You conclude your turn by discarding a card from your hand.

A round ends when a player has knocked. The other player may then lay down whatever melds they can, and add to the knocking player's melds. They do not take a card before this action, nor do they discard after.

Successive rounds are dealt and played until one of the players achieves the goal of 100 points to win the game.