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