Throw the hemp seeds, water, and salt in your blender, and blast on high for 30 to 60 seconds, until the seeds are completely pulverized. Use whole milk to maximize nutrition. Or strain for a smoother, more commercial-style milk for use in recipes.
To strain, place a nut milk bag or knee-high piece of sheer nylon hosiery over the opening of a glass bowl, jar or jug. Pour the milk into the bag, twisting the bag closed, and gently squeezing it to pass the liquid through.
Rinse your blender container, and pour the strained milk back in. Add the vanilla, sweetener, and any flavorings, and blast again, until smooth and creamy.
Store the milk in a sealed container in the fridge. Hemp milk will keep for about 3 days in a very cold fridge.