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