Finely chop the almonds, place them in a cheesecloth and nod it.
Bring the water to a boil, remove it from heat, insert the almond sack and infuse for 2 hours.
Remove the cloth, and squeeze and drain water as much as possible.
If you don't have or don't want to use a cheesecloth, blend water and almonds for a few minutes at the maximum speed, then strain the liquids through a fine sieve.
You may also have a second, less intense batch from the almonds you used to make almond milk without a blender: blend ½ liter (1/8 gallon) of water and the almonds you already used, for a few minutes, maximum speed. Strain through a fine sieve.
Add sugar and mix (hand blender, for best results).