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