Imagery consists of the use of symbols to convey an idea or to create a specific atmosphere. Shakespeare uses imagery in Macbeth often; pathetic fallacy, blood, tailoring and sleep are examples of this. His use of these tools in the play is to demonstrate the sadness of Scotland at what has been done, the guilt of the characters and to symbolises premonition of events.
Pathetic fallacy is a tool of imagery that is used in Macbeth to convey nature's response to the unnatural events that occur. Most of the scenes in which some kind of ill-doing is taking place is set at night or in darkness of some kind. Macbeth's murder of Duncan happens at night, and it triggers a response of outrage and grief in the land. Nature's troubled actions show us this; as Lennox tells Macbeth just before Duncan is found dead,
"The night has been unruly; where we lay, or chimneys were blown down ... lamentings head i' the air ... some say the ear was feverous and did shake." (II (iii) L59)
Another good example of imagery used is blood. It is used to convey guilt, murder, betrayal, treachery and evil. Macbeth, directly after his murder of Duncan, is concerned about the blood on his hands , and states that no amount of water will wash the blood away, signifying the guilt in his heart. Lady Macbeth, however, states "A little water cleans us of this deed" (II (ii) L97). It is ironic that later on in the play Lady Macbeth sleepwalks and dry-washes her hands, ands says "What! Will these hands ne'er be clean?" (V (i) L38) -- guilt at what she has done surfaces in her sleep where none was felt before, and the reverse is true for Macbeth.
The use of tailoring to convey the idea that something is not suited or not belonging to someone that has been acquired by them is used often in Macbeth. Macbeth himself uses the tailoring image in saying "The Thane of Cawdor lives: why do you dress me in borrow'd robes?" (I (ii) L109) when told by Ross that Duncan has given him the title Thane of Cawdor. This gives the impression that his newly acquired title does not fit him -- much like a garment belonging to another person. Angus states,