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