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