Set your policies, per booking type, that the customer must tick to say they have read and agree to the policy before they can proceed with their booking/enquiry.
Eg. "For bookings over 8 people we will contact you to collect card details, we will hold your table for 15mins, if you need to cancel your booking please contact us at least 24 hours in advance, over 21s only etc."
To add the Booking Policy to a particular Booking Type, head to Settings:
> Select Venue
> Booking Types
> select relevant Booking Type
> Scroll down to Availability section
> Fill out the Booking Policies column
The Booking Policy will display just above the 'Enquire Now' / 'Book Now' button the final window before submitting the booking/enquiry - see screenshot below: