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