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