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