Choose your Gallery via the menu in the left-side pane (click the +  to see the sub-categories).

In the Gallery view, click the Diashow button to start a diashow view of the current gallery.

In the Gallery view, click any thumbnail to see larger on the same page; scroll to the next set of thumbnails if applicable by clicking the '>' at the right of the thumbnails. 

Click the photo to view in full screen.

In full sceen view, navigate to the previous / next photo by clicking the < resp. >

Click the X to close the full screen and return to the gallery view

Use the 'share' options below any photo / gallery to share the content with your friends. You will find several sharing options.

Use the BUY button to obtain the full-sized image or postcard, calendar and more, all at great quality and against a very reasonable price :)