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