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