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