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