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