I've been using Sheila Water's practice method and it's turning out to be an excellent use of my limited time. It goes like this:
Divide your available time for the practice session into half. The first half is analytical practice, the second half is rhythmic practice.
For the Analytical half of your practice:
Using the piece you last wrote for your rhythmic practice, analyze:
* word and interlinear spacing, overall format
* letterforms by group (depends on the hand, but for example the round ones, branched ones and diagonal ones)
Then for each letterform group analysis, work on those letters together where you find issues. Keep checking and rewriting.
Work on serifs, loops, entrance/exit strokes, etc. (For your script, you'd work the basic strokes)
Work on ligatures/letter combinations, letter spacing, etc., esp. the troublesome ones.
For the Rhymical part of your practice:
Pick something to write, preferably full sentences/paragraphs.
Rule your paper, set up your margins, etc.
Warm up with a few lines of the basic strokes or primary letters that build the hand (e.g., for you the underturn, overturn, entrance stroke, arcades of u's and m's, ovals, etc.)
Using the same hand which you analyzed previously (don't switch hands during this session), write out the piece.
Keep the pace consistent whether it's an "easy" or "hard" letter.
Use only the knowledge in your hand and head about the script -- try not to look at an exemplar (you'll do that during the analysis of this piece next time).
Following this method not only helps organize your practice session in a systematic way that helps you learn from your mistakes, but also helps you build up a nice binder full of samples to look back over time and see improvement!
This is just a recap of her longer article on practice from her book "Foundations of Calligraphy."