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