Add the ashwagandha to your jar. Either cut or powdered herb will work.
Add the alcohol and water next. If they don't cover the herbs then add more water and alcohol mixture just until they do. Use 3 parts alcohol for every 1 part water.
Put the lid on the jar and store in a cool, dark place for 2-4 weeks. Shake occasionally during that time.
Once the tincture is done, strain out the herbs with a fine mesh strainer or cheesecloth and compost.
Add the filtered ashwagandha tincture to dropper bottles and store in a cool, dark place.
Notes
The standard adult dose is 1-10ml three times a day. This can be adjusted to your personal needs.
Alcohol-based tinctures last for years when stored properly.