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)(25,26,30,31,29,34,27,33)(28,36,35,40,38,39,37,32)(2,6)(3,4)(9,11,13,19)(10,14,16,17)(12,20,21,18)(15,23,24,22)(25,27,29,30)(26,31,34,33)(28,37,38,35)(32,36,40,39)(1,2)(3,8)(4,7)(5,6)(25,28,29,38)(26,32,34,40)(27,35,30,37)(31,39,33,36)(1,3,5,4)(2,7,6,8)(9,12,13,21)(10,15,16,24)(11,18,19,20)(14,22,17,23)(28,38)(32,40)(35,37)(36,39)(1,4,5,3)(2,7,6,8)(10,16)(14,17)(15,24)(22,23)(25,27,29,30)(26,33,34,31)(28,35,38,37)(32,36,40,39)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.