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