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