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