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