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