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