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