Step Process of Return Item from Customer, from warehuse receive until Credit AR Customer

Dear All
Can somebody tell me how to process Return Item On sales, which is this will effect on Sales, Account Receiveable and Inventory

If i'm not wrong I was read on RMA document, that I made Credit Order to Credit A/R customer
but it should be our warehouse receive first item of Customer return than after that Credit A/R customer

can somebody guide me the process from prepare and receive item return in warehouse until process for Credit A/R customer

Thanks

Juned