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