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