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