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