Step 1:) Login to your account: Login Here

Step 2:) Click on your completed orders: Completed Orders

Step 3:) Click on the View Order Details of the order you want to duplicate.

Step 4:) Select the checkbox next to the line item that you would like to re-order.  You must select at least one line item.

Step 5:) Click on Reorder Selected

Step 6:) Checkout in the normal fashion.