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