Making salt water on Shabbos:
A. For pickling foods:
It is forbidden to make heavy salt water [on Shabbos] or other liquids heavily salted in order to place [these liquids] into pickled foods, meaning [to place them in] vegetables or other foods which are pickled to be preserved (even if one plans to eat from them right away in which case he is not troubling himself for only a weekday purpose)
The reason for this is: See above Halacha 2B!
B. For dipping foods into:
Even to make salt water or other salted liquids not [in order to use] for pickling, but rather in order to dip ones bread into and to place it into a dish is forbidden to make a lot of it at a time, which is defined as making in one time enough for dipping for two meals, rather [one may] only [make] a small amount enough to for dipping for one meal.
Their reason: (is because when one makes a lot [at one time] it appears that he is doing so for pickling)
The condition that it must be made to eat right away: [Furthermore] even when making it for [only] one meal one is only allowed to make it in close proximately to the meal [in which one plans to dip in it], however [it is] not [allowed to be made] from [before] one meal for the need of another meal. [See Q&A]
The reason for this is: because it is forbidden to salt any item which one does not plans to eat right away.
One who places oil in the dish prior to the salt: [Furthermore] even if one places oil into [the dish] in between the placing of the water and the placing of the salt into it [in which case] the salt will not mix in well with the water and [the oil thus] weakens its strength of being strong salt water, nevertheless it is forbidden.
Salt water made of 2/3rds salt: If one places 2/3rds salt and 1/3rd water or other liquid, then it is forbidden to make even a small amount of it for the purpose of dipping in the upcoming meal. [See Q&A regarding making sugar water]
The reason for this is: being that it appears like one is making the Muryus gravy to pickle fish, as it is common to make Muryus in this way, [thus it is forbidden to make as] it is forbidden to pickle on Shabbos due to the tanning or cooking prohibition as was explained.
Summary-Making salt water or other salty liquids on Shabbos:
For pickling: Is Rabbinically forbidden to be done for pickling purposes.
For dipping foods: When done for dipping it may only be done if all the following three conditions are met:
- One does so right before the meal. [See Q&A]
- One makes just enough to dip for that meal.
- One has a ratio of salt that is less than 2/3.
These restrictions apply even if one places oil into the dish prior to placing the salt.
According to Admur may one make salt water even much time prior to beginning the upcoming meal?
No. The wording of “from one meal to another meal” written by Admur is not exact, as Admur already stated [above in Halacha 2 C] that it is forbidden to salt anything if one does not plan to eat it right away. Thus even for the upcoming meal salt water may only be made in close proximity to it.
May one make sugar water on Shabbos with two thirds being sugar?
The Kaf Hachayim, as well as other Achronim, write that it is forbidden. Practically this matter requires further analysis.
 Meaning he plans to eat some of them right away
 This follows the ruling of the Magen Avraham.
However the Mishneh Berurah [321/11] based on other Poskim [Elyah Raba] rules that it is allowed to be made even for later on, even for the need of another meal, so long as one plans to eat from it on Shabbos. [See Ketzos Hashulchan 128 footnote 9 which questions this ruling of the Mishneh Berurah.]
 Meaning that prior to placing salt into the dish one places oil into it.
 However the Mishneh Berurah [321/10] rules that one may be lenient if the oil is placed in prior to placing in the salt.
 Halacha 3
 Ketzos Hashulchan 128 footnote 9
 Ketzos Hashulchan 128 footnote 10