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