This wikiHow teaches you how to add photos and / or videos to a shared album using Google Photos on a computer.
Steps
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Step 1. Go to https://photos.google.com in a browser
If you are not logged in, click on "Go to Google Photos" to log in.
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Step 2. Click on ☰
This button is located at the top left and allows you to open a menu.
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Step 3. Click on Sharing
It is located towards the central part of the menu.
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Step 4. Click on the shared album
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Step 5. Click on the "Add Photo" icon
It depicts a photograph flanked by the "+" sign and is located at the top right.
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Step 6. Select the photos you want to add
Click on the circle located at the top left of the image to select it. Follow the same procedure to select all the photos you want to share.
To upload a photo from your computer click on "Select from computer", then choose the images you want to add and click on "Open"
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Step 7. Click Finish
This button is located at the top right. This way the selected photos and / or videos will be added to the shared album.