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