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