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