There are lots of examples of figurative language in "The Monkey's Paw." Firstly, there is an example of alliteration early on in the story just before the Sergeant-Major arrives at the house. Specifically, this is shown in the repetition of the "g" sound in the phrase "guilty grin."
Secondly, Mr. Herbert uses a simile to describe the way that the monkey's paw moves when he makes his first wish. He says, for example, that the paw moves "like a snake." This is not only an effective way of describing the movement, it is also suggestive of temptation and sin, just like the snake in the Garden of Eden.
Finally, there is an example of onomatopoeia at the end of the story. The narrator says, for instance, that the "stair creaked." This sound of a creaking stair is also an example of auditory imagery.