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