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