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