For chains, clean in simple green, soak then brush, scrub, maybe soak a bit more.
Rinse with hot(if possible) water, dry and set chains in a container of vinegar, cleaning vinegar 6% is nice however do not pay extra for it. It will go faster with a light scrubbing every once in a while. If it is super cold in the work space it will take longer. May off gas a bit of hydrogen, so be aware. Iron oxide will travel with the vapors so cover it or at least do not place on heirloom table cloth.
Rinse off vinegar using water with baking soda in it and then just hot water.
Dry chain, soak in bar lube. It will flash rust while you are watching it so move quickly.
In terms of time, the chain is ready when the chain is ready. Still stuck is not ready.
Hot water will make things go faster, not needed and does greatly increase fumes.
Wear some sort of chemical resistant gloves. Cover anything you do not want stained with iron oxide, if you are crafty folk the residue at the bottom of the vinegar container is almost pigment ready, so go nuts.
Do not get it in your eyes, mouth, nose, etc., just cause it is “natural” does not mean it is good for you.