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