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