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