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