How to track steps with the iPhone Health app
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Enable Motion Tracking, so that your iPhone will actually record the data.  Go to Settings&gt;Privacy&gt;Motion &amp; Fitness.  Toggle Fitness Tracking on. Now your iPhone will count your steps.

Go to the Health app to setup your physical info so that it can better estimate your stride length.
Add steps to the Today view.  While in Health app, go to the Health Data button at bottom left. Then tap Activity and scroll down until you find Steps and tap that. Toggle the Add to Favorites switch. Now you can view your step count easily from the Today screen.