Trigger workflow on PO Creation

Hi Experts,

I want to trigger a workflow when a PO is created( i.e Saved ). I have checked the tutorials that are available for PO release strategy, but my workflow is not getting triggered.

Note: i have tried by copying the standard workflow WS20000075, but doesnt work.

Can anyone provide the steps or some good document to send an email on PO Creation.

Thank You,