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