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