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