Tinctures are alcohol-based remedies for oral consumption. A Tincture is as much a dosage as it is a preparation; usually 10-20 drops of a Mother tincture diluted in a glass of spring/mineral water.
To make a Mother tincture using an airtight jar or container: Soak for a period of two weeks, fresh, dried or powdered plant parts in alcohol (traditionally brandy or a potin/vodka type spirit, herb to alcohol ratio is usually 1oz to 1pt or 25-30g to 500-600ml), strain liquid and store in an airtight dark glass bottle in dry press.
Premade tinctures are readily available from your local health store.