[The tune was unfamiliar to her, but Miriam didn't find it overly distracting or difficult to listen to him.]

You're right to be cautious; magic can be a double-edged tool. Incredibly helpful, and yet...dreadful, when turned against you.

[The fidgeting got worse as she said that last part. Miriam only realized it belatedly, and stopped with a sigh, leaving her poor sleeve alone.]

Practice will make control easier, as it will with most things. But as for a containment measure...

[She almost started picking at her sleeve again, and forced herself to stop.]

Those which I know of aren't guaranteed to work.