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