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)(12,15)(13,21)(14,16)(18,22)(19,23)(20,24)(1,3,6,5)(2,7,4,8)(9,11,14,12)(10,15,16,17)(13,19,22,20)(18,23,21,24)(25,26,30,35)(27,33,36,31)(28,32,38,39)(29,34,40,37)(1,3,6,5)(2,8,4,7)(10,16)(13,22)(15,17)(19,20)(25,27,30,36)(26,31,35,33)(28,34,38,37)(29,39,40,32)(9,12,14,11)(10,17,16,15)(13,20,22,19)(18,24,21,23)(25,28)(26,32)(27,34)(29,31)(30,38)(33,40)(35,39)(36,37)(1,4,6,2)(3,7,5,8)(9,10)(11,17)(12,15)(13,18)(14,16)(19,24)(20,23)(21,22)(25,27)(26,33)(28,37)(29,32)(30,36)(31,35)(34,38)(39,40)(1,5,6,3)(2,7,4,8)(9,13)(10,18)(11,19)(12,20)(14,22)(15,23)(16,21)(17,24)(25,29)(26,34)(27,32)(28,31)(30,40)(33,38)(35,37)(36,39)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.