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