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