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