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