Spades is a popular trick-taking card game played with a standard 52-card deck. It is usually played by four players in partnerships of two. The primary objective is to accurately bid the number of tricks you and your partner will take during a hand. Here is a detailed explanation of how to play Spades:

Setup

Players: Four players form two teams. Partners sit across from each other.
Deck: Use a standard 52-card deck (no jokers).
Dealing: The dealer shuffles the cards and deals them clockwise one at a time until each player has 13 cards.

Bidding

Objective: Each player must bid the number of tricks they expect to take. A trick is won by having the highest card of the suit led or the highest spade if spades are played.

Order: Bidding starts with the player to the left of the dealer and proceeds clockwise.

Bids: Players bid a number from 0 (Nil) to 13. Partners' bids are combined to form the team's bid.

Nil Bid: A player may bid "Nil" if they believe they will not take any tricks. This can be risky but offers high rewards if successful.

Playing the Game

Leading: The player to the left of the dealer leads the first trick. Players must follow suit if possible. If a player cannot follow suit, they may play any card, including a spade.

Trump Suit: Spades are always the trump suit. Spades cannot be led until they are "broken" (a player cannot follow suit and plays a spade).

Winning Tricks: The highest card of the suit led wins the trick unless a spade is played, in which case the highest spade wins.

Next Lead: The winner of each trick leads the next.

Scoring

Making the Bid: If a team meets or exceeds their combined bid, they score 10 points for each trick bid plus 1 point for each additional trick (called a "bag" or "overtrick"). Example: If a team bids 7 and takes 8 tricks, they score 70 + 1 = 71 points.

Failing the Bid: If a team does not meet their bid, they lose 10 points for each trick bid. Example: If a team bids 7 but takes only 6 tricks, they lose 70 points.

Nil Bid: If a player successfully bids Nil and takes no tricks, their team scores 100 points. If they fail, their team loses 100 points. The player's partner's tricks still count towards the team's bid.

Sandbags: Accumulating too many bags can lead to a penalty. For example, every 10 bags might result in a 100-point deduction.

Winning the Game: The game continues until a team reaches a predetermined score, typically 500 points.

Strategy Tips

Communication: Partners should try to gauge each other's hands through their bids and play, but direct communication about the hand is not allowed.

Bidding: Bid realistically based on your hand. Overbidding can lead to significant penalties.

Nil Strategy: Bidding Nil can be a high-risk, high-reward strategy. It requires careful play to avoid taking any tricks.

Trump Control: Manage your spades carefully. Keeping higher spades for critical moments can help you win crucial tricks.

For more details and variations of the rules, you can refer to resources like Bicycle Cards or Pagat.