Soya Milk

Soya milk is by far the most widely used alternative but not necessarily the best.
To make 1 liter of soya milk put 140 gm soybeans (idealy split soybeans) in a pan and pour 3 liters boiling water over them. Let it cool down and wait 6 to 12 hours. Drain the beans, add 1 liter cold water and mix it in a blender for 3 minutes. Remove the soymilk from the solids by squeezing the mixture through a cheesecloth. Bring the soymilk to boiling point and continue to boil for 10 minutes.
If you are making milks regularly, milkmaking machines are available in the US which are not very expensive and which are very efficient.