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