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