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