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