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