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