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)(11,17)(12,19)(13,16)(14,15)(18,24)(20,21)(22,23)(26,31)(27,34)(29,37)(36,39)(1,3,6,4)(2,7,5,8)(9,11)(10,12)(13,21)(14,19)(15,17)(16,24)(18,22)(20,23)(25,26,30,31)(27,28,34,32)(29,33,37,38)(35,36,40,39)(10,15)(12,17)(16,23)(20,24)(25,27,30,34)(26,32,31,28)(29,35,37,40)(33,39,38,36)(1,3,6,4)(2,7,5,8)(9,12)(10,11)(13,20)(14,17)(15,19)(16,18)(21,23)(22,24)(25,27)(26,28)(29,35)(30,34)(31,32)(33,36)(37,40)(38,39)(1,4,6,3)(2,7,5,8)(9,13)(10,16)(11,18)(12,20)(14,22)(15,23)(17,24)(19,21)(25,28)(26,27)(29,36)(30,32)(31,34)(33,35)(37,39)(38,40)(1,5,6,2)(3,8,4,7)(9,11)(10,12)(13,21)(14,19)(15,17)(16,24)(18,22)(20,23)(25,29,30,37)(26,33,31,38)(27,35,34,40)(28,36,32,39)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.