Publishing an album is to set it live for the clients to view them. It is easy!
Once you have uploaded all the photos in a given album, navigate to the top right side of the screen and find the Publish option.
Click on it and confirm that you wish to publish it, and your clients have it live to view and access that entire album.
The action of un-publishing an album after publishing it may be required if you have some additional photos to add, edit, remove or you simply don't want the clients to see the photos yet. In such cases, click on the album you want to un-publish, navigate to the top right corner of your screen and click on un-publish. Your clients will no longer be able to see that album until it is published again.