Correct request workflow

Hi

I have an urgent request!

It seems by now there is no chance to have Request Approval before task assignment. So I have to handle my flow in another way.
For example, I want a flow for request "Creating Username" .... My flow is like this (step by step):
      1. Create username in Active Directory ---------> being done by technician X
      2. Associate an account in Intranet website for the newly created username ---------> being done by technician Y
      3. Activate account for service request in SDP portal ---------> being done by technician Z

What is your suggestion to best implement this workflow?
Should advance the flow by changing technicians each level?

Amir