Scroll down until you find the ‘Custom promotions’ and then click on ‘Set up promotion’
Select 'Basic deal'
To make sure the promotion’s only accessible to guests who click on your BookingButton, select 'Only visitors on your direct channels'.
Set the length of stay, the booking dates, and policy, check that everything’s configured correctly, and click on ‘Activate promotion’.
If you want to deactivate your promotion, follow the steps in this article.
Note: All promotions that appear on Booking.com may be subject to experiments, so certain deals may only visible to some guests. These tests are a normal part of our procedures and are geared towards finding the best way to convert potential guests into bookers.