One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10)(11,17)(12,20)(13,16)(14,19)(15,22)(18,23)(21,24)(25,26,30,33)(27,34,35,40)(28,32,29,37)(31,38,39,36)(2,5)(3,7)(9,11,13,19)(10,14,16,17)(12,21,22,18)(15,24,20,23)(27,35)(31,39)(34,40)(36,38)(1,3,4,7)(2,6,5,8)(25,27,30,35)(26,31,33,39)(28,36,29,38)(32,40,37,34)(2,5)(6,8)(9,12,13,22)(10,15,16,20)(11,18,19,21)(14,23,17,24)(25,28,30,29)(26,32,33,37)(27,36,35,38)(31,40,39,34)(10,16)(14,17)(15,20)(23,24)(25,28,30,29)(26,32,33,37)(27,36,35,38)(31,40,39,34)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.