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