via Android to Shared Photos Album

BEFORE YOU START - Confirm that your photos are already stored in Google Photos on your phone. If not, add them from your Camera Roll to Google Photos.

Step 1: Click the View Album Link in your emai

Step 2: Join the Album as yourself

Step 3: Then it will look like this, with the option to Add photos

Step 4: Select the Photos from your Google Photos Album to be added to the Shared Album and click "Share"