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