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