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