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