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