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