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