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