One vertex per element, one color per generator, with an edge from x to x·s.
(2,5)(6,8)(9,10)(11,13)(12,14)(15,16)(17,18)(19,20)(21,23)(22,24)(25,26,30,31)(27,28,33,32)(29,34,37,38)(35,36,40,39)(9,11)(10,13)(12,16)(14,15)(17,19,22,21)(18,20,24,23)(26,31)(27,33)(29,37)(36,39)(10,12)(11,15)(17,19,22,21)(18,23,24,20)(25,27,30,33)(26,32,31,28)(29,35,37,40)(34,39,38,36)(1,2)(3,6)(4,5)(7,8)(9,12,14,10)(11,16,15,13)(17,20,22,23)(18,19,24,21)(25,28,30,32)(26,33,31,27)(29,36,37,39)(34,40,38,35)(1,3,4,7)(2,6,5,8)(9,13,14,16)(10,15,12,11)(17,21,22,19)(18,23,24,20)(25,29,30,37)(26,34,31,38)(27,35,33,40)(28,36,32,39)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.