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