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