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