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