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