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