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