General rules of soccer apply with following peculiarities             

        There are 5 players including goalkeeper on the field. Fewer than 4 players not permitted.
        The full game will take 2 x 15 minutes.
        No substitution limit at any time.
        Corners, side and free kicks must be kicked.
        A goal following a side-kick is not valid if the ball is not touched by any other player.
        Corners, side kicks and free shots must be kicked within 4 seconds.
          The oponent must be keep a distance of 5 meters.
        Goalkeeper's throw-in must be made by hand and not to land down behind the half line.
        Two yellow cards or one red card shown to the same player during the same match, means
         an expulsion. Substitution allowed after 3 minutes.
        A player can play only with one team.
        A player who playes with a second team will be consider out of the tournament and his team
         will undergo a 3-0 penalty on that game.
        A team not present within the scheduled time (15' of tollerance) or absent for any
          reason will loose 3:0.
        A goalkeeper cannot keep the ball with hands for more than 5 seconds.
        The number of sidelines player is unlimited.
        In case of points equality in basic groups determines:
          -  mutual match
          -  number of scored goals
          -  number of goals against
          -  3 penalty kicks
         In case of points equality of 3 teams determines the minitab of these teams.
        3 points win, 1 point ties

Warning:

To avoid any injuries, soccer shoes with metal studs are not allowed. Only shoes with rubber sole are accepted.