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