At what point can a solution be considered saturated?
OK.. well have you ever taken grade 11 chemistry you would know taht it is the maximum allowable dissolution of your solid (usually.. but for your question it is NaCl). Anyways in water you would have to find the specific Ksp for NaCl at the temperature you want, and then just add that much into a volumetic flask. then add distilled water.
If you are using another solvent, say NH3 then you would have to find the specific solubility of NaCl in that solvent. So start searching... or using a Merck or Physical & Chemical Handbook... cuz taht is easy... actually goto you libary since they need more ppl.
Also if you plan on making this thing... you could just freaking dissolve the maximum ammount of salt in solvent (pure)... anything that precipitates out.. means that the solution is "full".... but you really should have learned this.. in like grade school.... not from me