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