For one week only take the stairs–no elevators, no escalators. This may mean you have to walk a little further in a building to get to the stairs, but it will be worth it. Maybe by the end of the week you’ll want to take the stairs forever.
Do you work in an office building with some stairs? On your lunch break walk up a few flights–maybe five, maybe ten, maybe fifty. Listen to your body.
Have stairs in your house? At least one day a week make a point to go up and down them (carefully) five, ten, or fifty times.
Make notice of how many times you typically go up and down the stairs in your house.