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