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