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