I am more successful when I start with simple steps.
For me, motivation is not the key. Consciously in the present moment, doing one thing at a time is the key.
I do not require myself to get motivated to go for a walk. I just agree to put on my shoes.
I put them on and watch my hands as I lace my shoes.
As I walk, I listen to my feet hit the floor.
Then I agree to walk to a park bench a block away and agree that I can just sit on that bench if I prefer. Thirty minutes, forty-five minutes, an hour later I have finished my walk.