As you should. But don't be embarrassed about practicing! Nobody's born a master at it, even if someone happens to be really gifted at learning.

If you want to know a secret, I was only so-so at magic myself, I think, back when I was a healer full-time. Not enough to impress my teachers, at any rate. Nowadays I use the magic potential I have more defensively, for shields and the like. Normally, anyway; this is an exception.