Each player in clockwise succession declares their number of tricks until all players have bid. The player to the left of the dealer indicates how many books/tricks they will take.
The most common variations of spades use a standard 52-card deck. Note: these directions will be specific to the 4-player version. Variants (see below) exist for 2 and 3 players. The most common version of Spades involves 4 players: 2 teams of 2 players each.