To manually choose individual photos for your frame, open the Aura App and click into Photos, Collections or Albums. Select the photos for your Aura Frame by checking the small circle on the bottom right of each photo (a green check will mark the selected photos). All the photos you have checked will be added to Selected photos in the app.
You may also choose to sync photos using Smart Select which is available for Albums and Collections. Smart Select will filter your photos, displaying the best ones on your frame. If you have an Album or Collection set to Smart Select, any new photos you add to that album or photos you take of that person will automatically be uploaded to your frame.
The app also includes a Google Photos integration which allows you to connect your Google Photos account. Google photos offers unlimited storage and can store all of your photos from your Computer which can then be shared to the frame. When you open the Aura App, scroll down to where you see "Google Photos - Link Account" and select "Add Account". You are then invited to enter your Gmail address and password. Once this is complete you'll have access to all your Google Photos.