Sometimes, when I have 45 minutes or so and feel like having a unstructured, enjoyable and free-flowing, but technically effective practice session, I'll choose one of my memorized pieces or studies, and have what I call a creative practice session. In this article I'll show what I might do with the Study #1 of Heitor Villa-Lobos.
This study is the most famous and best of the arpeggio studies, so obviously our first goal is to make sure that the arpeggio pattern is accurate, relaxed, and even. The key word here, of course is relaxed, since everything comes from playing with the absence of tension. The only way to make as complex a motion as this one relaxed is by lots of repetition (only the best players really know how much repetition that can be). I'll usually start by playing the arpeggio pattern with the right hand (R.H.) only, settling the mind and relaxing the body. I will play extremely slowly, planting each R.H. finger before playing, feeling each attack, while at the same time switching my attention between how each note sounds, and how my body feels, perhaps altering the angle with which my nails attack the strings, or adjusting my sitting position, checking for muscle tension, in the neck, face, back, or even toes. For this study, I use the fingering pattern pmia pmia maim pipi, although I will try others, such as pmpm pmpm pipi pipi.
Once the arpeggio starts to feel relaxed, I'll start to warm up my L.H. I might play some scales, in this case E aeolian, in different positions. I haven't worked on the Segovia scales for a long time, instead playing position scales in thirds, fourths, or other digital patterns. Usually, I'll play some bebop licks, then improvise a bit, perhaps taking a specific lick or pattern and extending it, using it a a sort of seedling, and trying to grow other ideas from it. Using this process, sometimes you can create a wonderful idea, which can expand into a full composition.
Sometimes I'll go straight to the long descending diminished chord sequence (bars 12-23). This a good place to work on the arpeggio, since the L.H. is a parallel pattern, and doesn't require the shifting of attention back and forth between the hands. I make sure that each L.H. finger is well-placed, and make sure I've found the most efficient L.H. position. Also, after playing this section, the L.H. fingers are accurately grooved.
Because this is a six-string arpeggio pattern, any of these chords or chord sequences can be used for any six-string pattern. Here are the first two chords (Em - Am6/E), used in a nice milonga-like pattern:

When you play this pattern, be sure to play nice short, sharp staccato articulations by planting the m and a fingers immediately back on the top two strings. The aforementioned E aeolian mode works nicely as a basis for improvisation over these chords. Here is an example of what might be done over these chords: MP3 1.4 MB. I've stolen the simple two bar theme in octaves from another great contemporary composer. It may be a bit rhythmically cluttered, but is starting to sound pretty good to me.
The diminished chord in measure 12 sounds a lot to me like an E7b9, and resolves nicely to an Aadd9 chord. If you do the same thing two frets lower, then once more, you get the following progression: E7b9 - Aadd9 - D7b9 - G6/9 - C7b9 - Fmaj9. Voila! A new chord sequence with which to practise our arpeggio:

I wrote a little two bar melody to go along with this, but only over the first two chords, intending to mentally sequence it over the subsequent harmonies as I recorded it, but ended up improvising the last bit, and I think it sounds better this way. Listen, and play at this very slow tempo: MP3 790 KB. As I'm practicing and coming up with these ideas, I write some of them down, and come back to them eventually. If I think it's a good one I'll expand it into a study or full piece of some kind.
Since this is an arpeggio study, there isn't that much to draw on melodically. But isn't an arpeggio a melody? Here is a little elaboration on the famous descending slur section beginning in measure 24:

With another 50 bars or so this would make a nice Bachian prelude, or could be used as an introduction. This is what it sounds like: MP3 340 KB. Incidentally, this L.H. fingering was devised by the legendary Ida Presti, who was the duo partner of Alexandre Lagoya until her sudden death in New York City in 1967.
Well, I must admit that this little journey has taken me more than 45 minutes; I've spent considerably more than that on each of the three fragments. For those players who feel that their practice is getting a little stale, or have reached a point in working a piece or study where it seems a little too much like dull, repetitive labor, this is a great way to make it exciting again.
Peter Taschuk