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