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