You are able to create and offer promo codes to your customers, you can set this up under the "Set Up" page and choose on "Promo Codes":

Click on the "add new promo code" button:

Where you are able to set up the following information:

1.discount code name

2.discount amount (you can either use $ (amount) or % (percentage) of the service purchased)

3.discount applied - this can be applied per booking/per person

4.description of the discount code

5.expire after a certain number of uses - the promo code will stop working after it has been used that number of times indicated on the box

6.expire certain date -promo code will expire at midnight on the indicated date

7.services - this can be applied to certain services booked