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