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