Can my friend make their pair of insoles under my account?

No.

Each customer must create their own account, with their own email address and personal information. This will also keep each user's photos stored for future orders :D.

It is possible, however, to allow someone else to flow through the app on your iPhone, if by chance they do not have an iPhone or do not feel like waiting for the Android app to be released. They just need to create their own account :D.