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