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)(11,13)(12,16)(14,18)(15,20)(17,22)(19,23)(21,24)(25,26,32,36)(27,29,30,33)(28,35,31,34)(37,38,40,39)(1,3,5,8)(2,6,7,4)(9,11,14,20)(10,15,18,13)(12,19,22,24)(16,21,17,23)(25,27)(26,33)(28,37)(29,36)(30,32)(31,40)(34,38)(35,39)(1,3)(2,4)(5,8)(6,7)(9,12,14,22)(10,16,18,17)(11,19,20,24)(13,23,15,21)(25,28,32,31)(26,34,36,35)(27,37,30,40)(29,39,33,38)(1,4)(2,3)(5,6)(7,8)(9,12)(10,17)(11,19)(13,21)(14,22)(15,23)(16,18)(20,24)(25,29,32,33)(26,27,36,30)(28,38,31,39)(34,40,35,37)(9,13)(10,11)(12,21)(14,15)(16,24)(17,19)(18,20)(22,23)(25,30,32,27)(26,33,36,29)(28,37,31,40)(34,39,35,38)(9,11)(10,13)(12,19)(14,20)(15,18)(16,23)(17,21)(22,24)(25,31,32,28)(26,35,36,34)(27,37,30,40)(29,39,33,38)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.