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