Low fitness: Walk at a comfortable pace for 10 minutes around a mall or your neighborhood. Take a buddy and make sure you can talk as you walk.
Intermediate Fitness: Walk at a brisk pace, increasing walking time by 5 minutes every day or two. Use music with a good beat in a personal music player to help you increase your speed and time.
High fitness: Add weights, power-walk, jog or run. Work on increasing distance, time and speed.
Tip: A pedometer will help in every situation to measure steps and/or distance.