You can add a gloss finish to your photo product during the checkout process. Once you select "Order" you'll be redirected to the ordering page where you see the option to add the gloss finish.
Select "Yes, I'd like the high gloss finish" and continue with your order. For all other products, under "Paper Type" ensure the gloss option is selected.
There is an additional cost for a gloss finish which will reflect per page and vary depending on the size of your photo book or product you are ordering. You can find an overview of our prices here.
Also see: What is gloss finish?