There are many variations on the Rules and Regulations of Croquet, including competitive and social forms. The more competitive variations are the North American rules as developed by the U.S. Croquet Assocation and adopted by Croquet Canada, and the International Association rules as adopted by Croquet Canada. The North American and International Association rules vary significantly in many aspects but nonetheless use the same croquet equipment and court set up.
The Rules of Croquet:
See the World Croquet Federation
Croquet Rules Overview
Croquet can be played in many different ways - though likely not with a croquet set that features flamingo mallets and hedgehog balls, a la Alice in Wonderland. However, the Queen of Hearts might have enjoyed playing eXtreme croquet, in which players dispense with out-of-bounds rules and seek out playing surfaces that make St. Andrews in Scotland look like a mini-putt golf course.
Speaking of golf, golf croquet is one of the most popular new forms of the game. Just don't go trading in your favorite croquet mallet for a nine-iron and driver. Golf croquet features the same croquet balls and mallets as other croquet games, but teams/players compete to earn points by being the first and only ball to clear each wicket.
Chances are though that you're looking to enjoy a standard four-player croquet game or six-player croquet game. Croquet is usually played as a backyard lawn game, so the rules can be pretty casual, but croquetters who want to play the real thing should stick to these fundamental rules.
Teams & Order of Play
The point of croquet, of course, is to use your mallet to hit your ball through the wickets and into the stake(s), and finish doing so before your opponent(s). Croquet is usually played as a team guy, with two or three people to a side. The order of play is always blue, red, black, yellow, followed by green and orange if six croquet balls are being used. In team play, blue/black/green goes against red/yellow/orange.
Each player has one shot per turn but can earn extra shots by scoring a wicket or by striking another ball, which is known as a roquet. Scoring earns one bonus shot and roquetting earns two. New bonus shots can only be earned on the final bonus shot, and there's a limit of two at once. With the optional "deadness" rule, a roquetted ball can't be struck for a bonus again unless the striking player has first scored another wicket. If a ball stops out of bounds, place it inside the boundary in a direct line from its position.
Court size is officially 100 feet long by 50 feet wide for nine wicket and 105 feet long by 84 feet wide for six wicket, but who's counting? If you're playing nine wicket, which is known as backyard croquet, create a double diamond formation by placing a wicket at the exact center of the court, flanking it with opposing wickets on each side (about 16 feet up/down and 20 feet out from the exact center), and then add a wicket-wicket-stake setup at the center on each end (each six feet apart, with the stake six feet from the boundary line). If you're playing six wicket, which is known as American croquet, place a stake at the center of the court and then form two inward-facing wicket triangles on either end (the triangle tips facing the stake and the bases facing the top/bottom boundary lines).
Croquet wickets have to be run in the proper order and in the right direction.
Nine wicket: bottom two up, bottom right, center, top right, top two up, stake, top two down, top left, center, bottom left, bottom two down, stake
Six wicket: bottom left, top left, top right, bottom right, bottom center, top center, top left, bottom left, bottom right, top right, top center, bottom center (up), stake
Finally, with the rover ball rule, a ball that has scored all wickets but not staked out can be used to roquet balls. If it hits the stake or is knocked into the stake, the rover ball is out of the game. The "deadness" rule applies to rover balls, which must run ANY wicket in ANY direction to remove deadness.