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