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