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