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)(11,16)(12,19)(13,17)(14,23)(15,18)(20,21)(22,24)(25,26,29,32)(27,30,35,39)(28,31,36,40)(33,37,34,38)(1,3,5,4)(2,6,8,7)(9,11)(10,16)(12,17)(13,19)(14,24)(15,20)(18,21)(22,23)(25,27)(26,30)(28,33)(29,35)(31,37)(32,39)(34,36)(38,40)(9,12,14,16,15,22,13,21)(10,11,17,19,18,20,23,24)(27,33)(28,36)(30,37)(31,40)(34,35)(38,39)(1,4,5,3)(2,7,8,6)(9,13,15,14)(10,17,18,23)(11,19,20,24)(12,21,22,16)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.