Have you checked
this large thread on 3D printing here?
While you can obviously use a template, it may be better in the long run to design your own. Using your own printer, while still getting it working, you might find that certain polymers and temperatures cause things to change size with settings. Having designed your own 'hello world' model, you would be more comfortable modifying the model to your machine.
I'm not sure what your skill level is with CAD either. I've used keycaps as a way to practice with the different programs to find one that meets my needs and to get in valuable practice.
You are more than welcome to try my template, which you can find attached to
this post. It isn't perfect, but it might be a starting point.
What kind of a printer did your friend order?
