If you see an ENTER SHOP button at the top of the page, Click It first, then click the basket next to the eye on any items you wish to order.
 
If there is NO "Enter Shop" button at the top of the page, THEN JUST CLICK THE BASKET NEXT TO THE EYE ON ANY ITEMS YOU WISH TO ORDER

When you are ready to check out, just click "Checkout" to go to the secure credit card information page.