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