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