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