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