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