These writing quills have been used for centuries and they're not too difficult to make. Gather a few different size diameter quills, in this instance we used goose quills.
Strip them of their vanes
At this stage they are too soft to write with so they'll need to be tempered in hot sand
Keep them on a low heat for just a few minutes, you'll know when they're ready as they turn hard and slightly translucent, a bit like a finger nail.
Once you have them at the correct temper carve them into the shape you prefer for writing, this is a very personal thing and you might need to experiment to get the right nib shape for you. Luckily you can re-carve the quill quite a few times before you need to make a new one.