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)(11,14)(12,19)(13,15)(16,20)(17,23)(18,21)(22,24)(25,26,29,33)(27,32,35,30)(28,36,37,31)(34,38,40,39)(1,3,6,5)(2,7,8,4)(9,11,13,18)(10,14,15,21)(12,17,20,24)(16,22,19,23)(25,27)(26,30)(28,34)(29,35)(31,38)(32,33)(36,39)(37,40)(1,4)(2,5)(3,8)(6,7)(10,15)(14,21)(16,19)(22,23)(25,28,29,37)(26,31,33,36)(27,34,35,40)(30,38,32,39)(1,3,6,5)(2,7,8,4)(9,10)(11,14)(12,16)(13,15)(17,22)(18,21)(19,20)(23,24)(25,28)(26,31)(27,34)(29,37)(30,38)(32,39)(33,36)(35,40)(1,4)(2,3)(5,8)(6,7)(9,11)(10,14)(12,17)(13,18)(15,21)(16,22)(19,23)(20,24)(25,27)(26,32)(28,34)(29,35)(30,33)(31,39)(36,38)(37,40) involution — undirected(1,5,6,3)(2,7,8,4)(9,12,13,20)(10,16,15,19)(11,17,18,24)(14,22,21,23)(25,26)(27,30)(28,31)(29,33)(32,35)(34,38)(36,37)(39,40)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.