I am currently a player - druid lvl 5 with Nature, Medical and Survival skill proficiencies and I have proficiency with the Herbalism kit - and we had such a discussion with our GM, and we don't have a clear point of view of how crafting potions works. I mean, I know in game 2-3 basic ones (potion of healing, antitoxin for paralyzed poison, potion of climbing). I can "research" new ones by combining ingredients.
How can I learn new potion recipes?
Is this explained in the PHB or DMG? I couldn't find that.
Another solution and question about that: We have an artificier in game, who knows how to create potion of greater healing (Uncommon). Is it possible for him to make a formula for this potion and give me that formula? Thanks to that I could learn this recipe and create that on my own.
There is a high probability, that it is not clearly explained neither in PHB nor in DMG. Maybe someone of you have met with such a problem in yours campaign and can provide a solution. I would be interested in hearing all of them.
The answers in related question may be a guide for basic rules, but it is not referring to more complex potion crafting.