Take a look at this new book out on the basics of practicing and performing music.
You can read most of it here: The Musician's Way (google books preview)
And the author, Klickstein, also has an interactive and informative blog as well as a very useful set of musician's links to peruse.
Very informative and thorough. I've ordered a copy from Amazon.ca in paperback.
Other similar titles welcomed (although I've read a TON on this topic---I'm still actively seeking handy and pithy resources such as this for my University level music students.)
Great stuff. Very to the point.