How do you make the love potion? Or what do you have to do to get to the point to where you can learn to make it?
Some recipes can be found in Witch Hut - different during the day, different during the night. But it's a riddle, so it's not learned automatically like some other potions. It's for people to figure it out by themselves.
In case you prefer an easier way: LD - recipes
It's not a big guide, but it have information about recipes and ingredients.