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