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