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