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