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