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