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