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