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