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