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