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