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