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