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