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