When you check things off, you check or count them while referring to a list of them, to make sure you have considered all of them. Once you've checked off the items you ordered, put this record in your file I haven't checked them off but I would say that's about the number. = tick off
{f} tick off, tick, put a check mark, indicate that something has been done or completed by putting a check mark or a tick next to it
put a check mark on or next to; "Please check each name on the list"; "tick off the items"