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