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