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