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