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