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