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