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