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