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