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