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