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