Each player is dealt four face down cards and eight hand cards. Each player places four of their hand cards face up over the face down cards: one face up card on each face down card.
Now each player has four hand cards. The player with the lowest hand card plays that card in the center. The next person may now play a card equal to or higher in value than the last played. Each player draws one card from the remaining deck each time they play a card. Multiple cards may be played at a time as long as they are the same value.
If someone cannot play on the central pile, they must pick up the pile and then play any value of their choosing.
A 2 is a special card; it is not a low card. Instead, a 2 "neutralizes" the value of the pile, allowing the next person to play any value card they want on the pile.
A 10 is also special; it burns the pile unless the number is greater than 10; the pile is discarded and the last to play may now play what they want.
If someone plays all of their hand cards, they may now play the face up cards they reserved from the beginning instead of their face cards.
When a player plays all their face up cards, they move on to their face down cards. They cannot look at these cards and are forced to play them at random. If the card they play is lower than the value required, they must take up the pile and again use it as their hand cards.
The first to get rid of all hand cards, face up cards, and face down cards wins the round.
Optionally the winner gets to choose which piece of clothing is removed from the opponent, if you are playing a "strip" version of the game.
Some variations have it where when a card identical in value to the last is played, the next player in the turn order is skipped.
A very common variation is that when four of the same value card are played in a row, then the pile automatically clears.
Another very common variation is that when someone plays a 2 they can also play another card on top of it.
Some games state that if a seven is played, the next card must be lower than the 7.
Another variation is that instead of starting with four face-down cards and eight hand cards (four of which are put down), players only start with three and six or seven respectively.
In one version called Moonshine each player is dealt three cards face up, three cards face down, and five to be held in their hand. The cards left in the deck are to be draw from keeping five cards in your hand at all times, until the remainder of the deck is gone. The special cards are 2's which neutralizes the pile, 3's which are invisible so the next player must play on whatever card is under the three, 7's which the next player must play under and 7, and 10's which clears the piles and you get to go again. A four-of-a-kind also clears the pile and allows you to go again.