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