In Zadie Smith's novel On Beauty, one can find many different examples of literary devices in the text.
First, Smith uses descriptions of stock characters to allow readers to relate to characters being described. For example, in chapter one (in Jerome's e-mail to his father) he tells of a "yank intern" adding that the intern is from Boston. Many readers know what the term "Yank" means and can picture what this character would look and sound like.
One small literary device which also appears in chapter one is alliteration. While typically seen in poetry, alliteration is the repetition of a consonant sound within a line. Therefore, the words "Monty's," "much," and "more" represent alliteration given they repeat the consonant sound "m."
Jerome's comparison of his life to "a different universe" is a metaphor. A metaphor is a comparison between two, normally, unlike things.
When Jerome describes the house he is living in, the early Victorian, he uses very imagery ridden language. This use of imagery appeals to a reader's sense of sight and allows the reader to paint a mental picture of the house being described by Jerome.