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