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