To create a contract:

1. Go to Contracts and open "New Contract"
2. For rental contracts, select the property, then choose the customer. For other contract types (service, NDA, project), only a customer is needed.
3. Enter the contract name, amount, VAT rate, and recurrence
4. Set the start date and first invoice date
5. Add optional service details or auto-send settings if needed
6. Save the contract

You can open the saved contract later to review or adjust the billing setup.