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