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