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