The steps to create a Template (App, File, and EDI) are same and fixed. If you have more steps then you need to use the Custom template.
Using a Custom template, you can define your own process flow and publish it as a configurable Template. You can also dynamically select the steps for the process flow.
After creating a Template, you must activate and share it with your Partners. The Partners will use this shared Template to create a Transaction for exchanging data.
Using a Custom template type, you can create following two types of Templates:
Create an Inbound template to receive data from the Partner. In this Template, your Partner will define the Source application account and configuration details.
Create an Outbound Template to send data to the Partner. In this Template, Company will define the Source application account and configuration details.