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