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