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