Here is the menu for the recent food article in which I reported on three mornings of Cantonese dim sum. This menu is from Yulong Seafood Hotpot Restaurant in Macau, near Ponte 16. The dim sum article is here: https://www.chinese-forums.com/forums/topic/54982-enjoying-dim-sum/?tab=comments#comment-424075
(You can click the photos to enlarge them.)
The waitress brings a pencil along with the menu, and you put a check mark below the items that you want to eat. She told me it didn't matter which box I checked, one of which is for ordering an item a la carte 单点 and the other for ordering an item as part of a larger meal 加单。
She returns later with a typed receipt for the order as it was entered into their system. Always a good idea to double check at that point to be sure there was no mixup. Pricing category designations appear beside the name of the item: 特点，大点，中点，小点。
I always try to pick up a blank extra menu so I can study it at my leisure later in the day and do a better job of ordering tomorrow.