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