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