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)(11,17)(12,16)(13,14)(15,19)(18,23)(20,21)(22,24)(25,26,31,35)(27,32,36,39)(28,29,33,40)(30,34,37,38)(1,3,4,7)(2,5,6,8)(10,14)(15,17)(16,21)(22,23)(25,27,31,36)(26,32,35,39)(28,37,33,30)(29,38,40,34)(1,2)(3,5)(4,6)(7,8)(12,20)(16,21)(18,24)(22,23)(27,36)(30,37)(32,39)(34,38) involution — undirected(1,3)(2,5)(4,7)(6,8)(9,11,13,19)(10,15,14,17)(12,18,20,24)(16,22,21,23)(25,28)(26,29)(27,37)(30,36)(31,33)(32,38)(34,39)(35,40)(1,2)(3,5)(4,6)(7,8)(9,10)(11,17)(12,16)(13,14)(15,19)(18,23)(20,21)(22,24)(25,29)(26,33)(27,34)(28,35)(30,39)(31,40)(32,37)(36,38) involution — undirected(9,12,13,20)(10,16,14,21)(11,18,19,24)(15,22,17,23)(25,30,31,37)(26,34,35,38)(27,28,36,33)(29,39,40,32)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.