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