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)(9,11,13,24,14,25,15,23)(10,16,19,21,20,31,18,34)(12,22,27,38,28,39,29,37)(17,30,33,35,26,40,32,36)(1,2,6,5)(3,8,4,7)(9,12,13,27,14,28,15,29)(10,17,19,33,20,26,18,32)(11,22,24,38,25,39,23,37)(16,30,21,35,31,40,34,36)(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.