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