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)(13,17)(14,18)(15,20)(21,22)(23,24)(25,26,31,33)(27,32,37,38)(28,34,35,29)(30,36,39,40)(1,2)(3,6)(4,5)(7,8)(9,11,14,20)(10,15,18,19)(12,13,21,23)(16,24,22,17)(25,27,31,37)(26,32,33,38)(28,36,35,40)(29,30,34,39)(11,20)(13,23)(15,19)(17,24)(26,33)(27,37)(28,35)(30,39) involution — undirected(1,3,4,7)(2,6,5,8)(9,12,14,21)(10,16,18,22)(11,13,20,23)(15,24,19,17)(25,28)(26,34)(27,36)(29,33)(30,38)(31,35)(32,39)(37,40)(9,10)(11,15)(12,22)(13,17)(14,18)(16,21)(19,20)(23,24)(25,29,31,34)(26,35,33,28)(27,30,37,39)(32,40,38,36)(9,13)(10,17)(11,21)(12,20)(14,23)(15,16)(18,24)(19,22)(25,30)(26,36)(27,34)(28,38)(29,37)(31,39)(32,35)(33,40) 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.