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