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