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