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