As trained public health expert, this how I was trained to treat drinking water at domestic level:
I brought water to boiling point and keep it boiling for 15-20 minutes. This destroys all forms of micro-organism, including the most resistant spores or cysts. It does not require technical skill and any family can apply the method.
However, boiled water has one disadvantage and that is the flat taste [palatability] due to loss of dissolved gases [such as carbon dioxide and oxygen] during the process of boiling. This, I remedy it by keeping the boiled water for a few hours in partially filled containers or pouring the water between two clean containers several times to aerate it.
Then, I store it in a clean firmly covered container, preferably the same container in which it was boiled. Or my buckets with taps at the bottom to keep it wholesome-without pathogenic micro-organism or harmful inorganic salts.
Why I prefer raw water for bottled water; because I need solvent for maximum solubility in which transport of nutrients, gases and wastes products in my body to take place efficiently which bottled water being already a solute can not provide.