Get a pedometer. Walking is a self-reinforcing measure and motivator of your recovery.
Celebrate your milestones! Just stepping out of bed for the first time and standing on your own two feet counts as your first step. Even if there are more tubes coming out of you than you can count.
You will have about a five foot radius when you cross the 10 steps a day threshold. That might get you to the bathroom or out of bed to push a button.
Once you master the five foot radius, longer journeys of 100 steps (probably still indoors) are quite the adventure. My first 100 steps were to the ice machine in the hotel and back.
It was almost four weeks before I mustered my first 1000 step day. The picture above is where I walked. It was a great meditative, restorative walk on Pleasant Beach, along Rich Passage.