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