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