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