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