Make sure you have enough space: The throwing area should be about 5' wide and 11' long. You'll also want to think about wal space for a scoreboard and standing or seating room for other players and spectators.
Think about the floor: Darts will sometimes hit the floor. A hard floor like concrete will dull the tips of steel darts and softer floors can be damaged. Consider a protective dart mat.
Think about the wall: Less experienced players may not hit the board every time. Consider some type of extended protection around the board – maybe a wall saver.
Measure and Mark: The center of the dart board should be at a height of exactly 5' 8". The throwing line should be measured back from the face of the board. For steel-tipped darts, the line shoudl be 7' 9.25" back. For soft-tipped darts, the line shoudl be 8' back.