Makeup (Symbol)
Makeup is important to the play as the physical representation of beauty and youth. Lady Wishfort is the main character who interacts with makeup, and she notes its importance in the time leading up to the appearance of her supposed suitor, Sir Rowland, who has seen her in another physical representation of youth and beauty, a small painted picture of her. She feels the need to live up to this painted standard by painting herself.
Ms. Marwood's Letter (Symbol)
Ms. Marwood's letter is unseen until late in Act IV, but lingers as a symbolic element of the coming climax since the time she promises to write it after overhearing the scheme early in the play. When it does arrive in Lady Wishfort's hands, it physicalizes the gossip and back-stabbing that floats throughout and drives the plot of the play.
Alcohol (Symbol)
Alcohol is sometimes seen onstage, as in Lady Wishfort's dressing room, and sometimes implied to have been imbibed offstage. However, the effect of too much alcohol seems to be to lower people's level of propriety which is so important to social status in Restoration England. Thus, alcohol as a symbol represents the desire or ability to escape some of this rigid propriety, but can also be wielded in the schemes of others for this very reason.
Waitwell's "Sir Rowland" Outfit (Symbol)
Though there are not specific notations on the requirements of Waitwell's disguise as Sir Rowland, it can be assumed that his costume is the exact embodiment of an upper class fashion. Since Mirabell outfits him, it can be assumed that it will follow Mirabell's style to some extent, but as he is supposed to be Mirabell's uncle it will also have to be appropriate for an older age group. This physicalization of the costume element of fashion, as all fashion is just real-world costuming, calls attention to the silly and theatrical nature of society and physical societal signs of status.
Lady Wishfort's House (Symbol)
The fact that so much of the action is taken in one physical location demonstrates the closed of and near-incestual nature of upper class Restoration society. Because the action is so contained, gossip spreads quickly and fights can occur suddenly. Secret romance, too, is harder to hide in confined quarters, leading to situations like Ms. Marwood's spying from the closet, something that couldn't have happened unless the plot was largely confined to a single house.