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