Customer details can be added along with the order creation process. When type of order is selected, you can add customer details at that point also 
clicking on this will take you to add customer screen, where you can add customer details
- Add customer details to the order
- Once all the details are entered, click on “Save” button to finalize the changes
Customer details can also be added even when you have started adding items to your order. Click on the type of orderin the cart area
Clicking on this will take you to add customer screen, where you can add customer details