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