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