Integration between Salesforce and Workday: User Creation

In my project, I've built up the Salesforce-Workday integration.

I now want to construct user Accounts in Salesforce that map to the user information from Workday as the following step.

i.e. When a salesforce admin adds a new user's email address in Salesforce, after hitting the Save button, it should immediately begin looking for a Workday user with the same email address and auto-populate Salesforce user details with Workday user details.

Thank You.