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