Stop asking motivation to do the whole job
Motivation is useful for starting, but it changes from day to day. Make the decision smaller: choose a minimum walk that still counts, name two realistic times when it could happen, and prepare the shoes or route before the moment arrives. The goal is to reduce the number of decisions between you and the door.
Use a weekly target instead of a fragile streak
A daily streak turns one missed day into a verdict. A weekly target leaves room for weather, work, sleep, and recovery. Choose a number of walking days you can repeat during an ordinary week, then place them wherever the week actually allows.
Give the walk a second purpose
Attach walking to something you already value: an audiobook, a phone call, a quiet reset after work, an errand, or time outside. The walk becomes easier to repeat when it is not experienced as another obligation competing for your attention.
Make the result visible
Record completed walks somewhere you will see them. The record does not need to be public or elaborate. Its job is to turn a vague intention into evidence that you are becoming someone who returns to walking.