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