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