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