You are increasing the walking to 20 minutes this week. Now would be a good time to go to a running-specific shoe shop and get fitted with a pair of running shoes. Don't go too cheap as this will help prevent injury as you increase in distance.
This is a easy walk around the neighborhood or trails. Don't feel the need to 'walk fast'. You want to focus on your 'normal' pace.
This is your off day or switch with the next walk workout.
This is a easy walk around the neighborhood or trails. Don't go any longer than the time.