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)(11,14)(12,17)(13,18)(15,16)(19,21)(20,24)(22,23)(25,26,29,30)(27,31,34,37)(28,32,35,38)(33,39,36,40)(1,3,5,8)(2,6,4,7)(9,11,15,12)(10,14,16,17)(13,19,22,20)(18,21,23,24)(25,26)(27,31)(28,32)(29,30)(33,39)(34,37)(35,38)(36,40)(1,4,5,2)(3,7,8,6)(10,16)(14,17)(18,23)(21,24)(26,30)(28,35)(31,37)(33,36)(9,12,15,11)(10,17,16,14)(13,19,22,20)(18,21,23,24)(25,27,29,34)(26,31,30,37)(28,36,35,33)(32,40,38,39)(9,13)(10,18)(11,19)(12,20)(14,21)(15,22)(16,23)(17,24)(25,26)(27,31)(28,32)(29,30)(33,39)(34,37)(35,38)(36,40) involution — undirected(9,14,15,17)(10,11,16,12)(13,21,22,24)(18,19,23,20)(25,28,29,35)(26,32,30,38)(27,33,34,36)(31,39,37,40)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.