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