Scout says she doesn't mind being a ham for the performance, but the costume is not comfortable. Scout lists the many discomforts of her costume saying, "it was hot, it was a close fit; if my nose itched I couldn’t scratch, and once inside I could not get out of it alone." We know Scout wants to be as independent as possible, so her needing help to take off the costume is a major problem for her. This also hints that there may be a situation in which Scout's costume becomes problematic because she can't get out of it along. This literary device is foreshadowing - it's showing that some trouble might befall Scout because she can't get out of the ham costume.
