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