Uru will save your game automatically. You may continue your game from the last journey cloth touched by opening the linking book and turning the page. There you will see the Hand symbol of the last journey cloth touched. Click on it to continue. If you need to start an age over, simply destroy the book and pick it up again from the pedestal.
Please note - you will not be able to save until the linking book is found. You will need to pass the Cleft/Desert area.