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