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