Go to 'My Orders' > 'Orders' as shown in the top right hand menu.
Find the order and click 'View order'
Click 'Reorder' on the relevant product(s)
The product(s) will be added to your basket
Proceed to basket and checkout
The reorder option is available for registered users only.
To reorder, the original order must have been placed using the same account.
Reordered products cannot be edited or previewed prior to checkout, however the quantity and delivery information can be changed.