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