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)(11,17)(12,20)(13,15)(14,18)(16,21)(19,22)(23,24)(25,26,30,32)(27,34,28,38)(29,36,31,35)(33,39,40,37)(1,3)(2,5)(4,8)(6,7)(9,11)(10,14)(12,19)(13,18)(15,17)(16,22)(20,23)(21,24)(26,32)(33,40)(34,38)(35,36) involution — undirected(3,8)(5,7)(25,27,30,28)(26,33,32,40)(29,37,31,39)(34,36,38,35)(2,6)(5,7)(10,15)(11,18)(16,20)(19,24)(25,28,30,27)(26,34,32,38)(29,37,31,39)(33,36,40,35)(9,12,13,21)(10,16,15,20)(11,19,18,24)(14,22,17,23)(25,29,30,31)(26,35,32,36)(27,37,28,39)(33,34,40,38)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.