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