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