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