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