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