Pay attention to:
- Thickness: pick a pen that isn’t so thin that you end up having to squeeze it tightly, or so thick that it ends up being uncomfortable to hold.
- Tip size: pick a pen that has a tip size that you feel comfortable with (e.g. 0.5mm versus 0.9mm).
- Quality: use a good quality pen, that doesn’t require you to press hard on the paper in order to get the ink out.