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