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