You can upload a profile photo for an employee by following the steps below:
Search for the employee and go to their profile.
Click on the profile icon to the left of the employee's name.
Browse for the photo on your computer and either double click it or select it and click Open.
Refresh the browser page to see the change.
Once the photo is uploaded, it will also show as a file on the employee's profile, which you can see by following the steps below:
Search for the employee and go to their profile.
Click Documents and then Docs.
Expand the Person section. The photo will have the type set to 'Profile Image'.