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