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