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