Using the Order Settings Control Panel widget you can control the order process that users follow when they want to buy products.
This widget contains two primary sections: checkout steps and order emails. The checkout steps section allows you to add extra steps to the ordering process.
You can add custom steps to the order process, each of which can have custom fields. The values entered for these fields are then linked to the created order. Additionally, you can add custom fields to any of the existing steps. For instance, you can add a "agree to terms and conditions" label to the confirmation page if you wanted to.
Create a new step by clicking thebutton when viewing the list of steps. You can change the order of steps by clicking and dragging the step in the list of steps.
Some steps cannot have their order changed. For instance, the confirmation page will always come last.
The other aspect to managing the order process is to control emails that are sent. Using the Order Emails section, you can create any number of different emails. For example, you can create one email that is sent to an administrator when an order is placed, and a different email that is sent to the customer.
You can create emails for several different actions that occur: order placed, payment received, order shipped and order cancelled.
The email template must exist (using the template management tools) before you can add the new email to the order process.