Material Usage Variance for Particular Work Order.............

 Hii All,

Please help me on this. I want track material usage variance for each Work Order. When I am attaching part list to work order, standard quantities require for Work Order will get populated from BOM. While issuing to WO, I issued some less or more raw and packing material, so variance is tracked with WO. But suppose, there are some left over in production floor after production and I wanted to take back that material with work order, so that actual use of material will get track with standard for that particular work order. 

So, how to transfer this remaining material back to inventory with respect to that work order?