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