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