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