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