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