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