Here is a list of good habits that all musicians should have in their daily routine of practice and playing. Apply these to your practice time and be amazed!
1. Say your Music! Saying the notes and chords you are playing is like saying the ABC's in your mind. You will have music down as another language and therefore begin to speak it through your instrument. Many people that play music NEVER say the music. Then they wonder why they don't sound better. This skill is essential to realizing your full potential! “If you can say it, you can play it”!
2. Use a Metronome! Yes I know! It's hard to play along with. I've heard all the excuses in the world (including the ones I used to come up with). However, the point is this: If you want to be a good musician, you must use a metronome when you play your instrument. It's like having a "perfect" drummer there for you when you practice. It will correct you without saying a single word. It is "The Principle of Practice." The metronome never makes a mistake. USE IT!
3. Write your Music! This is an old as can be tradition, and that is the reason you must write your music out on paper. In today's world most people use computers, I know you are going to use your computer software to write your music, but writing with a pencil and manuscript paper is the best way for you to retain what you study and learn in music. For it is said: "to write it is to learn it three times." Imagine getting three dollars back for every one you save!
4. Know your Music! One may read this and say, "Well no kidding, of course I have to know the song I am playing." What I am saying here goes much deeper than just knowing the songs you play from memory. Every musician needs to know, from a theoretical standpoint, what every chord, note, and rhythm of the song means to that song and how it can be used and manipulated for interesting playing and application in other songs. You must know your chord structure, melody, and the correct rhythmic feel for the song you are playing. You have to know form, sound, and must develop your ears to hear music. Memorize them now so that you can use the tools for a lifetime. This is more than playing from memory!
-From Andy Hymel's "Music Theory Every Musician Should Know"