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