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