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