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