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