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