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)(11,18)(12,16)(13,22)(14,17)(15,21)(19,24)(20,23)(9,11)(10,15)(12,19)(13,20)(14,21)(16,23)(17,18)(22,24)(25,26,30,34)(27,35,37,32)(28,31,38,40)(29,39,36,33)(1,3,4,8)(2,5,6,7)(9,12,14,13)(10,16,17,22)(11,19,21,20)(15,23,18,24)(25,27,36,38,30,37,29,28)(26,31,39,32,34,40,33,35)(9,13,14,12)(10,16,17,22)(11,20,21,19)(15,23,18,24)(27,37)(28,38)(31,40)(32,35)(11,21)(15,18)(19,20)(23,24)(25,28,29,37,30,38,36,27)(26,32,33,31,34,35,39,40)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.