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