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