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