To produce an effective piece of writing, you need to bear your audience in mind. This is such a fundamental aspect of writing that literary critics have studied the process by which a piece of writing stages an interaction with its imagined audience under the names of dialogism, reader-response criticism or the implied reader. Essays which don't attempt to create a sense of audience are hard to distinguish from a collection of notes, since their only imagined audience is the writer. Writers can never really know who their readers are; the best they can do is to embody an idea of their audience in their writing with which readers will identify.
The writer's idea of the audience for which they are writing inevitably tends to differ from the impression the reader forms of the intended audience, but with experience writers learn to provide cues for the reader which explicitly indicate the kind of audience they have in mind, and so helps to bring the reader's idea of the audience closer to the writer's idea of the audience. Feedback is crucial to this process. The complicated interaction between the writer's idea of the audience, the reader's idea of the audience, and who the writer and reader actually are, forms an important context for the rhetorical situation occupied by a piece of writing, which can change as new readers come along.
You shouldn't think of your module tutor as being your "audience" in this sense - although your tutor will be reading your work, part of what they will be assessing is your success in conveying an idea of what you expect of your imagined audience through signposting. You'll find it more useful to think of the External Examiner as your audience.