Making your own oat milk is one of the cheapest ways to get dairy-free milk and with no need to soak oats overnight (as you do for almonds) it's also one of the quickest.
100g rolled oats
A few dates
1/2 teaspoon vanilla extract
1/4 teaspoon cinnamon
A small pinch of salt
Soak the oats in 500ml of cold water in a bowl. Leave for 15 minutes.
Place a sieve over a second bowl and pour the soaked oats and water through the sieve.
Stir the oats in the sieve using a wooden spoon so that the oat milk collects in the bowl underneath.
Once all liquid is drained from the oats, place the soaked oats back into the first bowl, and cover again with 200ml cold water. Leave for another 10 minutes
Draining all the oat milk from the soaked oats as above.
Use a jug or funnel to pour the milk into a large glass jar with a secure lid. Store the milk in the fridge for up to 3 to 4 days. Shake the jar very well before drinking.