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