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