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