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