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