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