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