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