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