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