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)(12,15)(13,16)(14,19)(18,23)(20,22)(21,24)(25,26,29,28)(27,31,34,36)(30,32,38,37)(33,40,35,39)(9,11,13,19)(10,14,16,17)(12,18,20,24)(15,21,22,23)(25,27,29,34)(26,31,28,36)(30,33,38,35)(32,40,37,39)(2,5)(6,8)(9,12,13,20)(10,15,16,22)(11,18,19,24)(14,21,17,23)(26,28)(27,33)(30,38)(31,39)(34,35)(36,40)(10,16)(14,17)(15,22)(21,23)(25,28,29,26)(27,31,34,36)(30,37,38,32)(33,40,35,39)(1,3,4,7)(2,6,5,8)(11,19)(14,17)(18,24)(21,23)(27,33)(30,38)(31,40)(32,37)(34,35)(36,39)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.