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