The dance floor is usually divided into concentric lanes, with the outside lane being described as the "FAST" lane. This is where you should be if you're Two Stepping or Waltzing. Depending on the size of the dance floor there may also be an "INNER" lane for slower dances such as a Schottische. If you are doing a slow dance, stay in this inner lane and let other dancers pass you on the outside. The closer you go to the center, the slower you may go. Line and Swing dancers are usually located in the center of the floor so it might be somewhat inadvisable to move too close to the center if you are doing a slow dance.
When Line Dancers are not on the floor then Swing dancers should take the CENTER or, if the floor is not large enough, the OUTSIDE CORNERS of the dance floor.
Always be courteous to other dancers on the floor. Couples should try to avoid bumps and bangs on the floor. The Follow probably can't see what's coming but the Lead can! If there is a collision always apologize (even if it isn't your fault). This usually prevents unnecessary unpleasantness and often leads to the forging of some great new friendships. However, don't make a habit of making new acquaintances in this way! If you collide with other dancers in a competitive environment you will be heavily penalized by the judges.
Men or Women with partners should ensure that both their first and their last dance is with his/her own partner. Common courtesy also dictates that if you see someone without a partner you should, as they said in the old days, "mark their card" and take the floor with them at least once. If you do dance with a different partner NEVER walk away from them after the dance has ended. Always walk them back to their seat.
It is always good manners to dance when asked. If, for some reason, you cannot dance at that moment, apologize, and BE SURE to find that person later on to dance with them.
If there is anything being used to define the dance floor, such as stanchions, ropes, cords, fencing, bars, etc., please honor them. Do NOT step over them, move them, or change them from their original position or intent.