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)(11,12)(13,21)(14,15)(16,18)(17,23)(19,22)(20,24)(25,26)(27,30)(28,36)(29,32)(31,38)(33,35)(34,40)(37,39)(1,3,6,5)(2,7,4,8)(10,15)(12,16)(17,21)(20,22)(25,26)(27,33)(28,31)(29,32)(30,35)(34,40)(36,38)(37,39)(10,15)(11,18)(17,21)(19,24)(25,26,29,32)(27,30,35,33)(28,31,38,36)(34,39,37,40)(2,4)(7,8)(9,11,14,18)(10,16,15,12)(13,19,23,24)(17,22,21,20)(25,26)(27,33)(28,31)(29,32)(30,35)(34,40)(36,38)(37,39)(1,4,6,2)(3,8,5,7)(9,12,14,16)(10,11,15,18)(13,22,23,20)(17,24,21,19)(25,27,29,35)(26,30,32,33)(28,37,38,34)(31,40,36,39)(1,5,6,3)(2,7,4,8)(9,13,14,23)(10,17,15,21)(11,19,18,24)(12,20,16,22)(25,28)(26,31)(27,34)(29,38)(30,39)(32,36)(33,40)(35,37)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.