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