One symbol that relates to the overall theme is the dress that Dee Johnson wears. Mrs. Johnson makes it clear that she and Maggie are accustomed to simple living, functional clothing made by hand. In contrast, Dee wears an ornate, colorful dress that serves as a symbol of her ostentatious lifestyle; she doesn't want to be connected to anything in her old life and so takes pains even down to her clothes to seem different.
A dress down to the ground, in this hot weather. A dress so loud it hurts my eyes. There are yellows and oranges enough to throw back the light of the sun. I feel my whole face warming from the heat waves it throws out.
(Walker, "Everyday Use," xroads.virginia.edu)
This description is contrasted with clothing that Maggie wears; a simple pink skirt and red blouse, just clothing with no other purpose than to cover and protect. Maggie knows enough of reality to not really care what she looks like; she is cowed by Dee, though, and is embarrassed to be seen in comparison. The extremely showy dress is a symbol of Dee's new lifestyle, her new outlook on life, and the difference between Dee and her family.