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