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