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