Question. How to collect wild oat grains, traditional way.

Hi,
I've discovered I have some wild oat in my garden. It's very little to make something with it but some bread toppings. However, I've tried to gather the grain from the seeds with a knife, and that's too much work for the benefits. It sure must be a traditional way to do this, but I can't find information in the internet.

Can anyone help me?
Thanks in advance.