Or you might say " I'm just waiting on the corner near Maccas" .

“我会在麦当劳附近的角落等待。”

Now if anyone asks you to do a Maccas run, it means go out and pick up McDonald's and bring it back for everyone.

如果有人要你 do a Maccas run，意思就是你要去买麦当劳，然后带回来给大家。