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