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