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