Click the little arrow next to your name in the top right hand corner, and choose My Settings. Changing your profile picture will change your card image in real time!
If you have already completed your course, you should have one of the snapshots taken during the induction automatically uploaded to it. Press the bin icon to the right of the image to delete it.
To insert another photo for your Digital Card, hit the Browse button. This will allow you to provide a new image file, which will be used to check your identity and your course completion.
The photo will appear on the screen so that you can adjust it. After you're done, don't forget to Save it.