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