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