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)(11,16)(12,17)(13,18)(14,19)(15,20)(21,22)(23,24)(25,26,30,34)(27,31,32,28)(29,33,38,37)(35,39,40,36)(2,6)(3,7)(11,20)(15,16)(21,24)(22,23)(25,26)(27,31)(28,32)(29,33)(30,34)(35,39)(36,40)(37,38) involution — undirected(1,3)(2,4)(5,7)(6,8)(9,11)(10,15)(12,21)(13,22)(14,20)(16,19)(17,23)(18,24)(25,27,30,32)(26,31,34,28)(29,35,38,40)(33,39,37,36)(1,4)(2,3)(5,8)(6,7)(9,11)(10,16)(12,21)(13,23)(14,20)(15,19)(17,22)(18,24)(25,26)(27,31)(28,32)(29,37)(30,34)(33,38)(35,36)(39,40) involution — undirected(9,12,14,18)(10,17,19,13)(11,21,20,24)(15,23,16,22)(25,28,30,31)(26,32,34,27)(29,36,38,39)(33,40,37,35)(9,13,14,17)(10,18,19,12)(11,22,20,23)(15,24,16,21)(25,29,30,38)(26,33,34,37)(27,35,32,40)(28,36,31,39)A 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.