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