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