In the case of Roy and Coral, the audience sees their reconciliation through the symbolic offering of the shells to Roy from Coral. With just stage directions, we can tell that this is Coral offering herself, her old self, to Roy. She is asking for forgiveness and we know through Roy's kissing of the shells and Coral herself that he has accepted her apology. The directions on the positioning of the characters on stage have to be effective to avoid audience confusion, as there is often split scenes.
The way the set is used ("use of space") is a useful medium to show conditions of the scene. These can include time of day, where the scene is set, the time period of which the scene was set, and the motives of the characters. Props are often included to add reality to the scene and often offer symbolism relating to the character that uses them. On Christmas Day at the campsite that Gwen's family is staying at, Gwen, rushes onto the scene with a 12-inch fake Christmas tree and announces "If you want to have a Christmas you'd better get started now so we can get it over with. Hurry up. I don't spending half the day sitting around waiting for people to open their presents." This Christmas tree, being fake, represents Gwen's resentment of Christmas- she obviously thinks it is a real chore. This does not make Meg and Jim's Christmas real- their they are, on a day that is supposed to promote goodwill, the importance of the family and other relevant values, and their mother and wife is acting like she'd rather be any other place than with them- this day is an inconvenience.
Characterisation can be defined as the representation of a character on the stage, especially by imitating actions, gestures, or speeches. Every element that combines to make a character is included in characterisation. Costumes are a helpful channel of symbolism and we can learn different things about the characters, both in connotative and deconnotative ways.