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