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