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