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