The document provides guidance on how writing a diary can help improve English skills. It explains that a diary allows the writer to focus on specific areas like tenses, vocabulary, and grammar. The diary example demonstrates use of past, present, and future tenses as well as highlighted phrases that add description, show cause and effect, and provide structure. The document encourages the reader to imagine an audience and add details about feelings and clarity of events to make the diary engaging like a higher level writer.