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