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