Oh, that's an interesting question. It might be an idea to have a go at some sturdy drinking straws for practice, because it's holding the quill which makes life difficult - more than actually shaping it. There's a big difference in feel between the cut you make to take the end off before soaking and curing, and the shaping cuts: the knife wants to skate off or else dig into the hardened quill so you have to work fairly briskly. Having worked up a bit of confidence cutting drinking straws would probably make it that much easier.
I have to say that although I can certainly make pens which write pretty well, they're hardly works of art to look at. Getting better though.

It's quite a steep learning curve, but really very satisfying.
If you have a body of water nearby now's the time of year to take a walk apparently, because it's moulting season. At least that's what the chap at the poultry farm told me - I'm lucky enough to have a ready supply on my doorstep.