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