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