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