Please see the above video for a brief description of how to play Eton Fives.
Eton Fives is played in a three-sided court with a step dividing the front and back portions. A buttress is located on the left hand side in line with the step, at the foot of which is a small hole called 'the pepperpot'. On the front wall, there is a ledge roughly 1.5m from the ground.
Each shot during the rally must be hit 'up', i.e. it must hit the front wall above this ledge in order for the rally to continue. The court also has many other ledges and features, including notably the 'bricks' at the back of the court which allow more complicated shots to be played.
Eton Fives is played in pairs, and during a rally the teams take it in turns to take shots, although for each shot, either team member may play on behalf of his team, as with tennis doubles.
Each game is played up to twelve points, with a final point called 'step' when a team reaches eleven points. However, different scoring systems are adopted if the teams are tied at ten all, as with a tie break in tennis. Points are scored by winning a rally, however you can only score points when your team is serving.
To begin a rally, one member of the serving team stands on top step next to the buttress and throws the ball around the top right hand corner of the court, so that it lands on the bottom step. One member of the other team then 'cuts' the ball back round into the buttress, ensuring that it hits the front wall above the ledge.
The game is designed to put the serving team at a disadvantage so that it is not easy to gain points. Therefore the person cutting can reject the serve as many times as they like. In addition to this, if the cut does not go above the ledge, the rally does not begin and the serve is replayed.
This means that the 'return of cut' (played immediately after the cut) is among the most difficult shots of the game.
Once the rally has begun, it continues until one team fails to hit the ball 'up', lets the ball bounce twice or hits the ball out of the court without it bouncing first. If the serving team wins the rally, they win a point, otherwise the server is defeated and the next player begins serving. The serving order is determined by the fact that you serve, then cut twice, then serve again except at the very beginning of each match.
A full set of rules for the game can be found here.