When selecting an item from the menu, a popup may appear that allows you to choose various toppings/ additions. At the bottom of that popup, there will be a field to include special instructions.
In some cases, an item will go directly to the cart after you select it. If this happens, you can click the item in the cart. Doing so will make a popup appear in which you can include special instructions.
Please note that you cannot request additional items in the special instructions. A restaurant will not be able to accommodate those requests.
On the checkout page, there is a field in which you can write special delivery instructions. These instructions will be available to your courier, so please include any information that they may find relevant.