If you have lots of the material, I think you would match it like you would for OBW. Find a feature on the fabric edge that repeats and put a pin in it. Find the same feature on the second fabric edge that matches. Lay them side by side after they are matched and check the design. If it is perfect, draw a chalk line 1/4 inch out from the sewing line. Match up the pieces and sew them. Caution: Some fabrics are not printed perfectly, some fabrics match down the fabric but not left to right. With the fabric you have chosen, I agree with others that sewing it unmatched would probably not be noticeable. Your backing fabric is a very pretty match for your lovely top!