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