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