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