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