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