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