Choose a dealer by whichever means.
Split the deck between both players, and both make the following stacks to form the tableau:
The remaining cards are the player's stock. Place them to one side.
There are no turns in Spit. Both players, on the count of 3, turn over the top card of their stock onto a new discard pile.
Using the cards face up on the tableau, and with only 1 hand, each player must place a card that is one value higher or lower than the top card of either discard pile. Colour and suit doesn't matter, and King wraps around to Ace.
You can only have up to 4 cards face-up at a time, meaning you will need to flip over cards in your tableau during play.
If no moves can be made then both players, on the count of 3, draw 1 card from the top of the stock pile and play it onto the discard pile. Play resumes.
Once your tableau is exhausted, claim a side (ideally the side with the fewest cards) and gather up that side's stock and discard cards. The other player claims the side not chosen.
Shuffle these cards together and deal out another tableau. A tableau may not have the required number of cards to complete.
The first player to lose all their cards wins.
In normal play, players must only use 1 hand to play cards. This rule can be relaxed to aid new players by allowing them to use both hands, or tightened by forcing a player to use their non-dominant hand.