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