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