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