Practice techniques...

I often see pianists discussing practice techniques on Twitter or their blogs. I was thinking about the different ways people practice today while I was practicing, and decided to write a blog post about it.

I use different techniques depending on what I'm aiming for in practicing, and the type of music I'm playing:

Technical work
Due to AMEB exams, I have to do a lot of technical work. Although I hate scales and arpeggios, I've figured out a practice schedule that works well for me and which I use as a warm-up, along with any exercises set by my teacher. 
I play scales hands together, three times (each with a different rhythm) and then normally. Then I'll go through the different versions - p and f, crescendo/diminuendo, staccato and contrary motion. I have to perfect each version of a scale (including all the rhythms) before I move on.
Arpeggios are similar - I practice each hand separately, playing them with different rhythms first, and then normally. Finally I put the two hands together. This process is almost as obsessive as metronome practice...

Metronome practice
This is the most obsessive and mechanical sort of practice I do. It's a technique I only use for Bach, Mozart, Haydn, the more strictly rythmic works of Ravel, and 20th century pieces. I almost never do metronome practice on Romantic pieces - I've tried it and it doesn't work for me at all.
Before I start the actual metronome work, I spend a couple of days (sometimes longer) learning the notes so I'm not sight-reading when it comes to practicing with the metronome, and also writing in fingerings. I have to be able to play the whole thing accurately at a slow tempo before I can actually get any further.
I then set the metronome to a slow speed (sometimes it's slower than half my intended performance speed, sometimes faster). Depending on the nature of the music, I might practice each hand separately first before practising with hands together (with contrapuntal music like Bach, it's essential that I get to practising with hands together ASAP.) I don't allow myself to move on to the next step on the metronome, or to move to a different hand, until I'm perfectly accurate. This process is repeated for each step up the metronome.
I usually manage between 1 and 3 steps up in speed per practice session, but that really depends on how much progress I'm making.
Metronome practice is one of those things I hate sometimes, but if I'm in the right mood, I actually really enjoy it, especially when I try playing the piece at full speed and it's improved so much.

Non-metronome practice
I use this technique with Romantic and Impressionist music, like Chopin, Mendelssohn and most Ravel. I start by just playing slowly and writing fingerings and notes in, a lot like the first stage of my metronome practice. If it's quite a technical piece, like the Chopin etudes, I usually do very slow, bar-by-bar practice to ensure I have all the notes under my fingers, and gradually speed up. But with pieces that have less of a solid structure (i.e. not just a heap of arpeggios and broken chords) I can usually manage to play the piece at full speed with very little slow practice, once I know the notes. Usually it's very specific, short passages that trip me up in these kind of pieces, so I might work specifically on certain passages to get them under my fingers.

Interpretative practice
I usually only do this sort of practice once I'm completely confident playing a piece at full speed, and often once I've learnt it from memory. This is the stage where I start working on how I want to interpret a piece. Often that involves overcoming new technical hurdles as well, so it can be quite involved.

On average I do 1 and a half to 2 hours of practice each day (well, I try to practice each day, but I don't always manage it!) I think the most practice I've ever done in one day is 4 or 5 hours straight. Sometimes I just get carried away and don't want to stop.

I'd be very interested to hear about other pianist's techniques for learning pieces...