To make coconut milk from coconut meat, pen up the coconut using a sharp chef's knife. Save the coconut water, and set aside. Using a spoon, scoop out all the meat from inside the coconut.
Using a fine grater, grate the coconut meat till everything is finely grated.
Add the grated coconut meat, coconut water and water. Blend on high for 2 - 4 minutes
Use a cheesecloth and strain as per the above method. Ensure you squeeze the cheesecloth till there is no more milk left in the coconut.
Discard the coconut, and transfer to a jar and refrigerate if not using immediately