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