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