The speaker begins the poem by refusing to compare his mistress's eyes to the sun. In the first line, he chooses this exaggerated simile to convey the absurdity of such comparisons in conventional love poems. Because he uses a negation, this can be described as a negative simile.
He proceeds by comparing her lips to red coral, stating that coral is far more red than her lips. This only makes sense, because the only way her lips could be as red as corals is if they are painted. This is another example of ridiculous comparisons in usual love poems.
While describing her breasts, he doesn't use a direct simile. Instead he simply lays two strong images before us; the white snow and the dun breasts. The white snow has a pure and clean connotation while the dun breasts, which are a grayish-brown, have somewhat of a dirty connotation.
A major cliché about women's beauty is that their hair should be silky and smooth. In line 4 the speaker describes his mistress's hair as black wires growing on her head. This may seem unattractive or even repulsive but he is crushing another traditional love poetry cliché.
The more clichés the speaker touches the more the reader realizes how ridiculous they are. He goes on to describe the lack of rosiness in her cheeks and the smell of her breath and the sound of her voice. The word "reek" here is used with the Old English