1. Be consistent. Pick a time every day that is designated for practice. For kids in school, practicing as soon as you get home from school, before you do your homework, can be a good strategy. Another good time is right after dinner. It's good to practice before too many other things can distract you.
2. Schedule your practice time. If you have a planner or a calendar program you use on your computer, make an appointment with yourself for practice, and set reminders so that you don't forget. I like to set alarms on my phone and computer for an extra level of reminding!
3. Break up your practice blocks. According to physical therapists, it's not good to play for more than 20 - 30 minutes consecutively. So, set a timer, then take a break, and then come back to it. If your goal is to practice 90 minutes throughout the day, you can do it in three 30 minute blocks. This makes it easier to focus and easier to fit in a busy schedule. Younger students can practice in three 10 minute blocks for a total of 30 minutes in a day.
4. Set goals. Set long term, medium, and daily goals. For example, when I was taking graduate auditions, my long-term goal was to get into a graduate school. My medium goal was to learn the whole first movement of the Tchaikovsky concerto. My daily goal was to learn the 2-3 pages of the concerto that I assigned myself. Setting goals helps you remember why you're practicing.
5. Make a plan. I find that the best way to practice is to make a plan as soon as you finish the previous day's practicing. It's much more productive than opening your violin case and going, "Well, what should I do today?" Look over your notes from your last lesson with your teacher. Think about what you practiced and what you would like to improve on tomorrow. Also estimate how much time each thing will take you. This way, you know exactly how much time to fit in your schedule for practicing.
Sample Practice Plan for a Suzuki Book 1 Student:
10 minutes: Warmups (violin hold and bow hold, bow games, finger taps and slides)
5 minutes: A Major Scale (pick 3 different Twinkle rhythms.)
5 minutes: Arm scrubs while singing through the Twinkle variations
10 minutes: Sing new piece, play practice spots, play new piece 5 times.
Further Practicing Resources for Students and Parents:
The Bulletproof Musician
The Musician's Way
Free Printable Practice Charts for Suzuki Students
Helping Parents Practice,by Edmund Sprunger
Practicing for Artistic Success, by Burton Kaplan
The Musician's Way, by Gerald Klickstein