One way to play solitaire is to start by taking 52 cards and dealing 13 cards off the top of the deck.
The person playing solitaire then arranges these thirteen cards into four piles – one pile containing four cards, three piles containing three cards, and one pile containing five cards.
The person then turns over one card at a time from the remaining pile of fifty-one cards. If this turned over card is not playable on any of the piles of thirteen, it is placed on top of the last pile.
If it is playable, you must move it onto one of the stacks. If it can be played on more than one stack, you have to choose which pile it goes on based on what will result in the least number of cards being left over.
Once you have dealt with the first face-up card, you then go on to deal with the rest of the face-up cards in this way – looking at each card that is turned up and moving it onto one of the thirteen stacks if possible, or leaving it there if not possible.
When you have dealt with all of the face-up cards, any cards that are left over go on top of the piles.
You then play another thirteen card level by dealing thirteen more off the top (the original pile should always be there ready for this, and you can move any extra cards from one or both of the other decks on to this original pile when they are dealt).
This continues until you get down to one card in each pile, at which point the game is won.
The shortest game possible (in terms of number of moves) is 28 moves. The longest game possible (in terms of number of cards left after dealing) can be as many as 559 moves.
Knowing ahead of time that a specific solitaire game will be the shortest possible or longest possible may not seem very valuable, but it can be helpful in certain situations.
For example, you might want to know if there is a winning strategy for a particular variant of solitaire so that you can adapt it to use for an automated solitaire game.
Or, if there is no possible winning strategy, you might want to know that so you can stop searching for one.
So this is how to play Solitaire.