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