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