Footbag Net Rules
From Footbag Reference
Footbag Net competition is governed by the Rules of Footbag Sports. The full rules are available in the online rule book which is notable available for translation into any language. (If you are interested in helping translate the rules into your languages, contact Steve Goldberg.)
The footbag net court is 44 feet long by 20 feet wide, with a 5-foot-high net in the center. (See picture.) More info here.
Footbag Net is played in a singles (one-on-one) or doubles (two-on-two) format.
In singles, two players on opposing sides of the net must return the footbag to the opposite side of the net using their feet in a maximum of two kicks per side.
In doubles, teams of two players on opposing sides of the net have a total of three kicks to return the footbag to the opposite side of the net. In addition, each team must alternate kicks, meaning the same player may not kick the footbag twice in a row before returning the footbag to the opposite side. It is not necessary for a team to use all three kicks to return the footbag to the opposite side of the net. (They may return in one, two, or three kicks; so long as they alternate.)
In Footbag Net, players must kick the footbag with a part of their body below the knees (i.e., any portion of the foot or shin). Any contact of the footbag to the upper body (e.g., knees and above) results in an "upper-body" foul and loss of the rally. Players must not contact the net or any portion of the supporting structures of the net during play. Players are allowed to reach over the net to kick the footbag, provided that they do not touch the net, do not touch their opponent on their opponent's side of the net, and do not cause an upper-body foul in the process.
Matches are often played in a best-of-three-games format, with each game ending at 15 points, or when one player scores more than 15 points and has two points more than his opponent. (In larger competitions, qualification and/or loser-bracket rounds may be played to 11 points instead.)
Service and Scoring
A rally starts with a cross-court serve from one team or player (on one side of the net) to the opponent. Points can only be earned by the serving player or team. When the receiving team or player wins a rally, the service switches to them. This is (as in volleyball) called a "side out". After a side out, the previous receiving team becomes the serving team, and can earn points.
During service, the court is further divided lengthwise into two halves. If the server's score is odd (e.g., 1, 3, 5, ...) he or she must serve from the back-left corner (outside the back line) to the far diagonal quadrant (where the receiving player must stand). If the score is even, the server must serve from the back-right corner to the far diagonal quadrant.
Service may only begin when the receiving player is ready (i.e., standing in the correct quadrant, and looking at the server). The server may not hide the footbag, during service, must call the score loudly, and wait three seconds before serving after calling the score. The server may not step on the back line or put his or her foot inside the court until the footbag has left his or her foot during service.
In doubles play, service is performed by the same player during a side out. However, each time the team regains the service, they must alternate which player serves.
More information with much more detail about the rules may be found in the Official Rules of Footbag Sports.