To edit or remove unwanted products from your cart, click on Cart in the right hand corner of your page.
Next to each product in your cart you'll see the price and "QTY" or Quantity.
To edit the Quantity, write the desired quantity in the QTY field. Then Click UPDATE right below that box. Your order total will adjust.
To Remove, click Remove below the QTY box and that item will be removed from your cart.