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