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