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