SubContracting process

We have two plants.

Plant 1 is ours one.

Plant 2 is subcontractoru2019s plant

We are subcontracting BOM components to subcontractoru2019s plant 2.

So how to do the entire sub contracting process cycle and also how to make the payment to the subcontractor for their service.

How to clear the payment for the subcontractor in FI side. Please explain me indetaily.

Thanks in advance