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