How to do MIGO & MIRO against a PO generated out of Value Contract.

Hi

I have made a value contract with a Vendor for supply of Office materials.

So i have used material group 006 with account assignment U - Unknown and Item caterogy as W - Material group.

I have made a PO with reference to the contract above and saved.

Now my question is

1. How to do MIGO

2. How to do MIRO

Regards

Maruthi ram