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