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