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