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