When hanging the board care must be taken to ensure that the floor does not slope away from the wall. If it does, the height of the bullseye will not be located the correct height from the floor in relationship to where the player is standing. If this is the case, the location of the dart board on the wall will have to be adjusted either up or down whichever the case may be.
When measuring the distance from the dart board to the toe line along the floor from the wall, care must be taken to include the distance from the wall to the front surface of the dartboard in the measurement to ensure proper placement. This procedure can be facilitated by tying a weight such as a large nut to a length of string and using it as a plumb bob by placing the other end of the string on the board's surface and letting the weight dangle near the floor. Place a mark on the floor with a piece of chalk and use this as the starting point for measuring the distance to the toe line.
An easier method is to measure diagonally from the center of the bullseye to the floor 2.931m (115-3/8"). This will reduce the margin of error as long as the bullseye has been placed at the correct height and the floor and the wall make a right angle.
The National Darts Federation Of Canada (NDFC) specifies that the minimum length of the toe line must be 610mm (24") long. Furthermore, a raised oche is specified and must be a minimum of 38mm (1.5") high. Although a raised oche is preferred, in most applications, the toe line is a length of tape place along the floor parallel to the wall the dart board is mounted on.