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