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