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