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