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