Simple but fun. The bug where a correct ingredient is counted as an error is kinda annoying. I find that it helps making the potions really slowly... maybe some sort of hitbox issue where the game thinks I'm holding something else or something? not sure...
But in general the strategy is to make a column of 4-5 potions before you start the day, and you make them slow enough so you don't trigger the meter too much. If you do you can always just wait a bit for it to go down to a safe level and try again then.
I'm curious about the new version that the dev mentioned in the comments though :D