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