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