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)(25,26,30,35)(27,31,37,40)(28,33,29,34)(32,38,39,36)(1,2)(3,6)(4,5)(7,8)(9,11,14,20)(10,15,17,18)(12,19,13,21)(16,23,22,24)(25,27,30,37)(26,31,35,40)(28,38,29,36)(32,33,39,34)(2,5)(6,8)(9,12,14,13)(10,16,17,22)(11,19,20,21)(15,23,18,24)(25,27)(26,32)(28,36)(29,38)(30,37)(31,34)(33,40)(35,39)(2,5)(6,8)(10,17)(11,20)(16,22)(19,21)(25,28,30,29)(26,33,35,34)(27,36,37,38)(31,32,40,39)(1,3,4,7)(2,6,5,8)(9,13,14,12)(10,16,17,22)(11,21,20,19)(15,23,18,24)(25,28,30,29)(26,34,35,33)(27,36,37,38)(31,39,40,32)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.