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