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