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