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