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