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