How to give clear, concise directions that others will understand and remember.

[edit] Steps

Make sure you know the way yourself.
Know exactly where the person seeking directions is starting from, and whether they are familiar at all with the area.
Recognize that men tend to use cardinal directions (i.e. north, south, east or west). Women tend to use landmarks. Tailor your response to the individual you are addressing.
State how far until the first turn either in blocks, miles, or the number of minutes to the first direction change. (if traffic is a major factor, do not use minutes.)
Mention whether the person needs to be in a particular lane.
Tell the person what direction they need to turn in before telling them where (e.g., "turn left on baker street" instead of "at baker street, turn left").
Repeat steps four through seven as necessary to get the person to his or her destination.
Mention which side of the street their destination will be found on. (for example - Go two blocks. Turn right on Jackson Avenue. Go approximately 3 miles. Turn left at the light onto Ambassador Rd. At the third traffic light turn left just after the car dealership. You're going to make the first right hand turn you can make. There will be a sign for RENTAL PROPERTIES. If you get to the bridge, you've passed it. The office is in the green building on the right hand side about fifty yards ahead.)
Ask if he or she understands and have him or her repeat the directions back to you.
Summarize in a simplified way, such as, "right, left, left, right" and have the person repeat that back to you.

[edit] Tips

If the location of a turn is easily missed, give a piece of information for the person to know s/he has gone too far. (If you get to the underpass, you've gone too far.)
If the person is present with you, have him or her turn in the direction s/he is headed, and use hand signals to reinforce the directions. The more senses you use, the more likely the person is to remember.
Draw a simplified map if paper and pencil are available.