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