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