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