Click on Edit.
Rearrange the photos using the mouse. To make a photo the main one, mark it with a star.
Save the changes.
The changes will come into effect within five days.
Please note: photo content standards are applied to Emerging Travel Group sites, therefore, the final order of the photos may differ a little from the one you set. These adjustments are required in order to display the most attractive images first and raise the probability of booking.