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